On October 8, 2014, Head Constable Vijay Singh awoke before dawn and scurried across the ochre gravel outside the constabulary barracks here at the Madras Atomic Power Station “looking like the monsoon was about to break,” as a ground sweeper later recalled. Singh was one of 620 paramilitaries in the country’s Central Industrial Security Force assigned to protect the facility’s nuclear-related buildings and materials, but he did not have his usual tasks in mind that morning.

By 4:40 a.m., the 44-year-old officer reached the armory, where he signed out a 9mm sub-machine gun and 60 rounds of ammunition in two magazines. Singh loaded one clip into his weapon, pocketed the other, and entered the portico of a cream-and-red, three-story residential complex. He climbed up one flight to the room where a senior colleague, Mohan Singh, dozed and abruptly opened fire at him in a controlled burst, to conserve rounds, just as he had been trained.

Then he jogged downstairs, where he shot dead two more men and seriously injured another two. With ten rounds left in his magazine, and an unused 30-round clip in his pocket, he prowled unimpeded across the gravel, with no alert called. A bystander shouted out to him, and suddenly Singh halted and dropped to his knees, an eyewitness recalled later. He was finally surrounded and led away, glassy-eyed, “as docile as anything, a neat guy, his hair still perfectly parted,” the witness said.

The episode was a fresh example of what officials here and outside India depict as serious shortcomings in the country’s nuclear guard force, tasked with defending one of the world’s largest stockpiles of fissile material and nuclear explosives.

An estimated 90 to 110 Indian nuclear bombs are stored in six or so government-run sites patrolled by the same security force, according to the Stockholm International Peace Research Institute, an independent think tank, and Indian officials. Within the next two decades, as many as 57 reactors could also be operating under the force’s protection, as well as four plants where spent nuclear fuel is dissolved in chemicals to separate out plutonium to make new fuel or be used in nuclear bombs.

The sites are spread out over vast distances: from the stony foothills of the Himalayas in the north down to the red earth of the tropical south. Shuttling hundreds of miles in between will be occasional convoys of lightly-protected trucks laden with explosive and fissile materials — including plutonium and enriched uranium — that could be used in civilian and military reactors or to spark a nuclear blast.

The Kalpakkam shooting as a result alarmed Indian and Western officials who question whether this country — which is surrounded by unstable neighbors and has a history of civil tumult — has taken adequate precautions to safeguard its sensitive facilities and keep the building blocks of a devastating nuclear bomb from being stolen by insiders with grievances, ill motives, or in the worst case, connections to terrorists.

Although experts say they regard the issue as urgent, Washington is not pressing India for quick reforms. The Obama administration is instead trying to avoid any dispute that might interrupt a planned expansion of U.S. military sales to Delhi, several senior U.S. officials said in interviews.

The experts’ concerns are based in part on a series of documented nuclear security lapses in the past two decades, in addition to the shooting:

•Several kilograms of what authorities described as semi-processed uranium were stolen by a criminal gang, allegedly with Pakistani links, from a state mine in Meghalya, in northeastern India, in 1994. Four years later, a federal politician was arrested near the West Bengal border with 100 kilograms of uranium from India’s Jadugoda mining complex that he was allegedly attempting to sell to Pakistani sympathizers associated with the same gang. A police dossier seen by the Center states that ten more people connected with smuggling were arrested two years after this, in operations that recovered 57 pounds of stolen uranium.

•Then, in 2003, members of a jihad group, Jamaat-ul-Mujahideen, were caught in a village on the Bangladesh border with 225 grams of milled uranium — allegedly illicitly purchased from a mining employee — that they said they intended to wrap around explosives. The Indian authorities initially claimed it was from Kazakstan but concluded later it was more likely from a uranium mining complex at Jadugoda, in eastern India.

•In 2008, another criminal gang was caught attempting to smuggle low-grade uranium, capable of being used in a primitive radiation-dispersal device, from one of India’s state-owned mines across the border to Nepal. The same year another group was caught moving an illicit stock of uranium over the border to Bangladesh, the gang having been assisted by the son of an employee at India’s Atomic Minerals Division, which supervises uranium mining and processing.

•In 2009, a nuclear reactor employee in southwest India deliberately poisoned dozens of his colleagues with a radioactive isotope, taking advantage of numerous gaps in plant security, according to an internal government report seen by the Center.

•And in 2013, leftist guerillas in northeast India illegally obtained uranium ore from a government-run milling complex in northeast India and strapped it to high explosives to make a crude bomb before being caught by police, according to an inspector involved in the case.

The paramilitary Central Industrial Security Force (CISF), which has a total of 95,000 personnel under civilian rather than military control and a $785 million budget, is supposed to keep all these nuclear materials from leaking from India’s plants. But it is short-staffed, ill-equipped, and inadequately trained, according to a confidential, draft, Home Ministry report about the force’s future, dated November 2013, seen by the Center for Public Integrity.

“Weapons supply is down by 40 percent, and training equipment by more than 45 percent” compared to what officials running the force had sought, the report stated. Its size should be twenty percent larger, it added. “Morale is low as security levels remain high …. There is a danger of the force falling behind in terms of its level of equipment and also competence.”

A former three-star Indian Police Service officer, who ran a large Indian force under the Home Ministry alongside the CISF, said in an interview that the force’s training, weapons and technical equipment lagged well behind comparable security forces elsewhere in the world. “From passive night goggles that cannot see in low light to outmoded communications equipment that does not work over long distances, they’re as good as blind and dumb,” said the ex-officer. “The monies promised two years ago to overhaul it … mostly failed to materialize,” he claimed.

This critical account roughly matches what the U.S. intelligence community has stated in its annual classified rankings of global nuclear security risks, based on detailed assessments of safeguards for materials that could be used in explosives or “dirty bombs” laced with radiation, according to three current or former senior Obama administration officials.

They said that India’s security practices have repeatedly ranked lower in these assessments than those of Pakistan and Russia, two countries with shortcomings that have provoked better-known Western anxieties. In all the categories of interest to the U.S. intelligence experts making the rankings — the vetting and monitoring of key security personnel, the tracking of explosives’ quantities and whereabouts, and the use of sensitive detectors at nuclear facilities and their portals — the Indians “have got issues,” a senior official said, speaking on condition he not be named, due to the diplomatic sensitivity of the issue.

Cautioning that Washington probably does not know everything that India has done to protect its facilities because of its obsessive nuclear secrecy, the official said that according to “what we can see people doing … they should be doing a lot more.” He added that it is “pretty clear they are not as far along as the Pakistanis,” explaining that as with the Russians, India’s confidence in being able to manage security challenges by themselves has repeatedly closed them off to foreign advice not only about the gravity of the threats they face but about how to deal with them.

Poor safeguards against the insider threat

When U.S. officials made their first-ever visit to the restricted Bhabha Atomic Research Center in Mumbai, a complex where India makes plutonium for its nuclear weapons, their observations about its security practices were not reassuring. “Security at the site was moderate,” a cable from November 2008, approved by embassy Chargé d’Affaires Stephen White, told officials in Washington.

Identification checks at the front gate were “quick but not thorough,” and visitor badges lacked photographs, meaning they were easy to replicate or pass around. A security unit at the center’s main gate appeared to be armed with shotguns or semi-automatic Russian-style rifles, the cable noted, but as the U.S. delegation moved towards the Dhruva reactor, where the nuclear explosive material is actually produced, there were no “visible external security systems.”

White’s cable noted that a secondary building where engineering equipment was stored also had “very little security.” While there was a sentry post at a nuclear Waste Immobilization Plant that processes radioactive water, no guards were present, and visitors’ bags were not inspected. No security cameras were seen inside, White added. The cable was disclosed by Wikileaks in 2011.

A U.S. nuclear safety official, also on the visit, who still works in the field and was not authorized to discuss it, told the Center in an interview that “laborers wandered in and out of the complex, and none of them wore identification.” He said that “the setup was extraordinarily low key, considering the sensitivity,” explaining that guards could not see camera footage from other locations. There is little evidence that conditions have changed much since then, officials say.

U.S. and Indian officials also have privately expressed worry about the security surrounding India’s movement of sensitive nuclear materials and weaponry. An industrialist who provides regular private advice to the current prime minister about domestic and foreign strategic issues said in an interview, for example, that due to India’s poor roads and rail links, “our nuclear sector is especially vulnerable. How can we safely transport anything, when we cannot say for certain that it will get to where it should, when it should.”

The adviser said that as a result, fissile materials in India have been moved around in unmarked trucks that “look like milk tankers,” without obvious armed escorts. He called this “urban camouflage,” meant to avoid the clamor that would ensue if a security convoy attempted to navigate traffic-choked roads like the one leading from a nuclear fuel fabrication plant in Hyderabad, in south-central India, to a test center for India’s nuclear submarines on the coast at Visakhapatnam. An armed convoy, he said, might need 14 hours to traverse that 400-mile distance.

Experts say the movement of the vehicles is tracked by special devices and communications. But two recently-retired scientists from BARC echoed the adviser’s concern in interviews. “Using civilian transport is a case of making the best of the worst: Far better not to be noticed at all, if you cannot control the environment you’re traveling in,” one said. Western officials have said that Pakistan uses similar unmarked convoys to move its nuclear materials, without obvious protections.

Official inquiries into the Mumbai attack in 2008, where ten Pakistan gunmen laid siege to the city after arriving at night by boat, showed that nuclear installations close to the city were staked out as potential targets before the terrorists settled upon a Jewish center, a railway station and two five-star hotels.

But to date, most of the troubling incidents at nuclear facilities in India have involved insiders, making the presence of aberrant employees the most tangible threat and the focus of intensive government efforts, according to a presentation made by Indian experts at a U.S. National Academy of Sciences workshop on nuclear security in Bangalore in 2012. They said that CISF forces assigned to protect India’s nuclear materials get extra training and are rotated regularly among such sites, possibly to deter corruption. Ranajit Kumar, the head of the Bhahba center’s physical protection system section, told the workshop that anyone who takes a new assignment on any classified project is supposed to undergo a new background check.

But an internal government report about the shooting here in Kalpakkam, drafted by officials in the Home Ministry, and dated December 2014, warned that many warning signs about Vijay Singh, the perpetrator, were ignored. It said that despite having an explosive temper and telling a doctor he was suffering from stress and exhaustion — issues that forced his withdrawal from weapons duties — Singh was promoted to the rank of head constable due to staff shortages and sent here from another nuclear installation without any psychological assessment or records recounting his problematic behavior.

At his new posting, he was given access to a submachine gun even though colleagues considered him unwell, as they told investigators later. He complained of being picked on by another head constable, and as the Diwali festival approached in October he asked for leave to visit his family. He was refused and instead ordered to serve overtime, due to a public call by Al Qaeda’s leader to “raise the flag of jihad” across South Asia by targeting sensitive sites in India. When the CISF officer’s final bid for leave was turned down, he told a colleague that “he would burst like a firecracker,” a colleague told police, in a witness statement seen by the Center — and one day later, he did.

Similar lapses had occurred seven years earlier when an employee at the Kaiga nuclear reactor deliberately poisoned several others, subjecting them to a radiation dose 150 times that in a chest x-ray. A report completed in December 2009 by the plant’s operator, seen by the Center, pointed to failures in technical monitoring as well as a “human reliability program” that was “ineffective if not misconceived” by the plant operator. Security cameras were not fixed on the key areas of the installation, and some were immobile and incapable of operating in the dark. It said the contamination was “an act of deliberate sabotage,” and that the perpetrator had eluded detection and capture due to numerous security lapses.

Asked about these matters by the Center, India’s Atomic Energy Commission declined to reply, following its usual habit of rebuffing inquiries about sensitive, nuclear-related matters. The AERB initially pledged to offer responses but then declined, as did the Home Ministry, which oversees the CISF.

Spurning U.S. offers of help

Since Nov. 30, 2001, when the CIA began investigating rumors that Al Qaeda was trying to obtain nuclear materials or finished weapons to be used against the West, the U.S. government has campaigned around the globe — sometimes unsuccessfully — for heightened vigilance in India and other countries with substantial stockpiles of explosive materials.

According to the International Panel on Fissile Materials, an independent, nonprofit group, India’s stockpile of about 2.4 metric tons of highly-enriched (weapons-usable) uranium puts it at fifth place among all nations, and its stock of approximately 0.54 metric tons of separated (weapons-usable) plutonium puts it at ninth place. But its security practices put it even higher on the list of Western anxieties.

The Nuclear Threat Initiative, a nonprofit group in Washington, reported last year for example that India’s nuclear security practices ranked 23rd among 25 countries that possess at least a bomb’s-worth of fissile materials. Only Iran and North Korea fared worse in the analysis, which noted that India’s stockpiles are growing and said the country’s nuclear regulator lacked independence from political interference and adequate authority.

It said the risks stemmed in part from India’s culture of widespread corruption — which helped force the nation’s ruling Congress party from power in May 2014 — as well as its general political instability. “Weaknesses are particularly apparent in the areas of transport security, material control, and accounting, and measures to protect against the insider threat, such as personnel vetting and mandatory reporting of suspicious behavior,” the group’s report stated.

But India has rebuffed repeated offers of U.S. help. Gary Samore, President Obama’s coordinator for arms control and weapons of mass destruction from 2009 to 2013, said that at preparatory meetings for international summits on nuclear security in 2010 and 2012, “we kept offering to create a joint security project [with India] consisting of assistance of any and every kind. And every time they would say, to my face, that this was a wonderful idea and they should grasp the opportunity. And then, when they returned to India, we would never hear about it again.”

India also refused to collaborate with the Nuclear Threat Initiative project by sharing or confirming information about its practices, unlike 17 of the other 24 countries in the study. They responded ferociously to its conclusions, according to a researcher connected to the project, who was not sanctioned to talk about it. Officials at the Indian Atomic Energy Commission verbally attacked Ted Turner and Sam Nunn, the NTI’s founders, in conversations with Indian journalists, the researcher said.

In countries such as India that are resistant to hearing direct U.S. advice, the Obama administration has tried what an official referred to as a “work-around” — the creation of training centers around the globe where Western experts working in collaboration with the International Atomic Energy Agency can encourage better safeguards. Twenty-three such centers, deliberately named Nuclear Security Centers of Excellence in a bid to get local buy-in, have been created so far.

The Indians “are happy to be in a place to have a conversation about nuclear security that is not judgmental,” a senior Energy Department official said, explaining the concept behind placing such a center in India.

But internal U.S. government cables asserted several years ago that while India initially seemed to embrace the idea, it eventually rejected it, to Washington’s surprise. In a Feb. 22, 2010, cable disclosed later by Wikileaks, then-U.S. ambassador Timothy Roemer said that instead of focusing on nuclear security, India finally decided to set up “a research and development center dedicated to the world-wide deployment of nuclear reactor technologies” that the country likes, but experts in Washington consider dangerous on grounds that they could contribute to the use and spread of nuclear-explosive materials.

The center “would be an Indian government body, staffed by the Department of Atomic Energy, whose primary focus was research and development” on new reactors, Roemer wrote. This approach “did not fully meet the U.S. vision,” he added. India subsequently renamed the facility its Global Centre for Nuclear Energy Partnership, and it began limited operations this year with closed workshops on the physical protection of nuclear materials and facilities scheduled alongside nuclear advocacy seminars entitled “Splitting Atoms for Prosperity” and “Atoms for Progress.”

Despite the celebration of close U.S.-Indian ties during President Obama’s visit to Delhi in January, “there is still no deep technical relationship” between the two countries on nuclear security issues, a White House official conceded in a recent interview, speaking on condition of anonymity. “We only hope that this will slowly change.”

At the moment, India is seeking three favors from Washington: It wants U.S. help to gain membership in the Missile Technology Control Regime, an international forum meant to limit the spread of nuclear-tipped missiles, which would give it access to certain otherwise restricted foreign space-launch technologies. And it wants to join the Nuclear Suppliers Group, composed of nations that agree to respect nonproliferation rules when they trade in nuclear-related technologies. Both ambitions reflect India’s desire to be accorded the status of a major world power, U.S. experts say.

It also wants to acquire U.S. defense technologies by co-producing weapons systems in India with key Pentagon contractors – an issue discussed between Secretary of Defense Ashton Carter and Indian defense minister Manohar Parrikar during the minister’s weeklong visit to Washington beginning on Dec. 4.

But the Obama administration decided not to use these issues as leverage to force better security measures for nuclear explosives, the senior U.S. official said, because of its judgment that doing so would only prompt India to walk away.

A former senior U.S. nonproliferation official said this was a mistake. Washington, he said on condition of not being named, “has allowed itself to be put into the position of not wanting to displease India for fear of putting things off-track” in its new, warming relationship, and it has wrongly “allowed the Indians to wall off things they are not interested in talking about” while its ties to the United States grow.

An official in Britain’s Foreign Office, who also spoke on condition he not be named, expressed a more jaundiced view of this reluctance to press Delhi harder.

“Nothing can be allowed to get in the way of investment in the capacious Indian market,” the British official said, describing the current American mindset. “India has effectively bought itself breathing space, over a lot of concerning issues, especially nuclear security, by opening itself up for the first time to significant trades with the U.S. and Europe.” The financial gains, he said, are “eye-watering.”

According to the U.S. Commerce Department, trade with India grew from $19 billion in 2000 to more than $100 billion in 2014. U.S. exports exceeded $38 billion — including substantial new U.S. arms shipments — supporting 181,000 U.S. jobs. Indian direct investment in the United States totaled $7.8 billion while U.S. investments reached $28 billion.

Washington, the British official explained, does not wish to provoke a spat over nuclear security simply because doing so could threaten this lucrative trade, which benefits many U.S. companies.