India's Operation Sindoor has fundamentally altered the nuclear equation between India and Pakistan, challenging long-held assumptions about nuclear deterrence in South Asia. The unprecedented military strikes by India against Pakistani targets have not only demonstrated India's resolve to counter cross-border terrorism but also sparked intense speculation about the safety and control of Pakistan's nuclear arsenal.

Despite official denials from both countries, reports of suspected strikes near Pakistan's Kirana Hills nuclear facility and the subsequent deployment of specialised radiation monitoring aircraft have raised significant questions about nuclear security in the region. This report examines the complex aftermath of Operation Sindoor, focusing on the renewed international scrutiny of Pakistan's nuclear weapons program and the potential implications for regional stability and security.

Operation Sindoor represents one of the most significant military engagements between nuclear-armed neighbours since the end of the Cold War. India launched coordinated precision strikes against Pakistani targets on May 7, 2025, in response to an April terror attack in Jammu and Kashmir's Pahalgam that killed 26 civilians. What makes this operation historically significant is that it marks the first time one nuclear power has conducted such extensive conventional strikes against another nuclear power without triggering nuclear escalation.

The operation included strikes on airbases in Sargodha and Nur Khan, as well as other military sites across Pakistan and Pakistan-occupied Kashmir. These strikes damaged radar systems, communication facilities, and airfields according to Indian officials. The scale and depth of these strikes demonstrates a calculated gamble by India that Pakistan's nuclear threshold was higher than previously assumed. Prime Minister Narendra Modi, in his first speech since Operation Sindoor, made it clear that India's doctrine on terror had forever changed, putting terrorists and their supporters in Pakistan on notice that India would strike again to protect its territory and citizens.

India's willingness to conduct deep strikes into Pakistani territory, despite the risk of nuclear escalation, suggests that Indian strategic planners have developed substantial confidence in their ability to manage the nuclear dimension of the conflict. This marks a significant departure from decades of strategic restraint that had characterised India's response to cross-border terrorism since both countries became declared nuclear powers.

Kirana Hills: Pakistan's Secretive Nuclear Facility


Kirana Hills, often referred to as the Black Mountains, is an 80-kilometre-long hill range located in Pakistan's Sargodha district, approximately 170 kilometres from the Indian border. This remote, heavily fortified zone has long been suspected of playing a crucial role in Pakistan's nuclear weapons program. Pakistan's defence ministry took control of Kirana Hills around 1970, and the site is now part of the Mushaf airbase, which houses Pakistani aircraft including F-16s and JF-17s.

Intelligence assessments and academic research suggest that Pakistan began using Kirana Hills for its nuclear mission around 1978-79. According to a 2023 report by the Bulletin of the Atomic Scientists, Kirana Hills served as a subcritical nuclear test site used by Pakistan for developing its nuclear program between 1983 and 1990. During this period, Pakistan reportedly conducted a series of "cold tests" or subcritical nuclear tests at the site, which simulate nuclear explosions without triggering fission reactions. These tests were critical for Pakistan to refine its nuclear warhead designs without requiring large underground test sites.

The strategic importance of Kirana Hills extends beyond its historical role in Pakistan's nuclear development. The site is believed to house at least ten underground storage facilities, munitions storage areas, and Transporter Erector Launcher (TEL) garages. Its proximity to key military installations, including the Sargodha Air Base (approximately 20 km away) and the Khushab nuclear complex (around 75 km distant), underscores its sensitive nature in Pakistan's defence infrastructure.

Speculation About Strikes And Radiation Concerns

Following India's precision strikes, speculation surged across social media and international media outlets regarding a potential nuclear radiation leak from Pakistan's Kirana Hills region. These concerns were amplified by unverified claims that Indian airstrikes had targeted this sensitive area, possibly affecting nuclear storage facilities. Though both India and Pakistan officially denied that Kirana Hills was targeted during Operation Sindoor, several factors contributed to the persistence of these rumours.

An inadvertent comment by Air Marshal AK Bharti, Director General of Air Operations for the Indian Air Force, fuelled speculation. When asked at a press briefing whether India had struck Kirana Hills, he responded with apparent sarcasm: "Thank you for telling us that Kirana Hills houses nuclear installations. We didn't know about it. We have not hit Kirana Hills, whatever is there". This ambiguous statement, while technically a denial, raised eyebrows among international observers.

Adding to the intrigue was the reported deployment of a specialised US radiation monitoring aircraft over the region. Flight tracking data from platforms like Flightradar24 reportedly showed a Beechcraft B350 Aerial Measuring System (AMS) aircraft, tail number N111SZ, briefly within Pakistani airspace. This particular aircraft type belongs to the US Department of Energy's fleet designed specifically for detecting radioactive contamination in emergency scenarios. Its deployment abroad is rare and typically requires diplomatic clearance and a clear purpose.

The B350 AMS is equipped with sophisticated gamma ray sensors, real-time data transmission capabilities, and advanced mapping tools that can analyse the spread of radioactive materials while conducting low-altitude, slow-speed flights. Its historical deployment in significant nuclear events, including the Fukushima disaster and for post-blast monitoring during US nuclear testing, made its apparent presence in Pakistan particularly noteworthy.

Some open-source intelligence analysts claimed that the aircraft in question had actually been transferred to Pakistan's Army Aviation in 2010. This revelation presented two possible scenarios: either Pakistan, fearing radiation exposure, deployed its own (formerly US) nuclear response aircraft, or the aircraft was deployed in coordination with the US to assess potential nuclear damage. Either scenario suggested a level of concern about possible nuclear contamination.

IAEA Clarification And Official Denials

Amid growing international concern, the International Atomic Energy Agency (IAEA) issued an authoritative statement on May 15, 2025, confirming that no radiation leak or release had occurred from any nuclear facility in Pakistan. "Based on information available to the IAEA, there has been no radiation leak or release from any nuclear facility in Pakistan," a spokesperson for the agency said in a statement issued in response to queries. This official clarification from the global nuclear watchdog helped to quell some of the more alarming speculation.

Both India and Pakistan maintained consistent official positions denying any strikes on nuclear facilities. Indian Air Marshal AK Bharti explicitly stated, "We have not hit Kirana Hills, whatever is there". Similarly, Pakistan's Director General of Inter-Services Public Relations (ISPR), Sharif Ahmed Chaudhary, dismissed claims that Pakistan's nuclear establishments had been targeted by India.

Despite these official clarifications, the speculation about potential nuclear implications of Operation Sindoor highlighted the inherent risks of conventional military operations between nuclear-armed states. The international community's rapid response-including the apparent deployment of specialised radiation monitoring capabilities-underscores how seriously such risks are taken, even when both sides deny nuclear dimensions to the conflict.

India's Changing Doctrine On Nuclear Blackmail

A significant outcome of Operation Sindoor has been India's explicit rejection of what it perceives as Pakistan's strategy of nuclear blackmail. For decades, Pakistan's nuclear arsenal has been viewed as a shield enabling its support for cross-border terrorism without fear of major Indian retaliation. Operation Sindoor appears to have fundamentally challenged this assumption, with Indian leaders making clear that Pakistan's nuclear status would no longer constrain India's response to terrorism.

Prime Minister Narendra Modi, in a pointed message following the operation, declared that India would not tolerate "nuclear blackmail" by Pakistan and would continue to punish cross-border terrorism strongly. This statement signifies a major shift in India's strategic thinking, suggesting that the traditional restraint exercised in response to terrorist provocations may no longer apply. Modi also stated that India would not engage in talks with Pakistan on Kashmir except to disable terrorist infrastructure in that country and arrange for the return of illegally occupied Kashmir.

The success of Operation Sindoor in achieving its military objectives without triggering nuclear escalation may embolden India's position that it has effectively called Pakistan's nuclear bluff. This could fundamentally alter the strategic calculus in South Asia, potentially reducing the coercive value of Pakistan's nuclear arsenal in any future confrontations.

Conclusion

The aftermath of Operation Sindoor has brought renewed international scrutiny to Pakistan's nuclear arsenal and raised fundamental questions about nuclear deterrence in South Asia. While speculation about strikes on Pakistan's Kirana Hills nuclear facility has been officially denied by both countries and the IAEA has confirmed no radiation leaks occurred, the episode has nevertheless highlighted the inherent dangers of conventional military operations between nuclear-armed states.

India's apparent success in conducting significant strikes without triggering nuclear escalation has emboldened its leadership to explicitly reject what it perceives as Pakistan's nuclear blackmail strategy. 

Defence Minister Rajnath Singh's unprecedented call for IAEA supervision of Pakistan's nuclear weapons, while diplomatically provocative and practically unfeasible, signals India's growing confidence in challenging the strategic status quo.

As both countries adjust to this new reality, the international community must remain vigilant about the potential for miscalculation or escalation in future crises. The long-rumoured existence of US contingency plans to secure Pakistan's nuclear weapons in extreme scenarios underscores the persistent concerns about nuclear security in the region. While Operation Sindoor may have concluded with a return to ceasefire, the nuclear dimension of India-Pakistan relations remains a critical concern for regional and global security.

IDN (With Agency Inputs)