In this photograph taken on Aug. 2, 2012 Indian Border Security Force (BSF) soldiers stand guard along fencing near the India-Pakistan Chachwal border outpost. Pakistani troops on Jan. 8, 2013 killed two Indian soldiers near the tense disputed border in Kashmir. (STRDEL/AFP/GETTY IMAGES)

Indian military officials on Tuesday accused Pakistani troops of killing two of their soldiers and mutilating the body of at least one of them after crossing into Indian territory in the disputed Himalayan region of Kashmir, a development that could impede a tenuous peace process between the nuclear-armed rivals.

The charge came two days after Pakistan accused India of killing one of its soldiers along the Line of Control, the de facto border where a fragile cease-fire has held for almost a decade.

Indian Defense Ministry spokesman Lt. Col. Rajesh Kalia said in a statement that the alleged incident marked “a significant escalation” of cease-fire violations by Pakistan and would be addressed “sternly” through official channels.

A senior Indian army official said that the body of one soldier killed in a firefight after the incursion had been badly mutilated and that the condition of the other remained unconfirmed. Some reports, citing military officials, said the head was missing from at least one of the bodies.

“This is not something of a very slight nature that you can bypass or ignore easily,” Foreign Minister Salman Khurshid told the Indian news channel NDTV 24X7. “It causes a tremendous amount of hurt to us. This is not the way that civilized people deal with each other, even if they have serious differences.”

The two countries are allies but their relationship has been plagued by mistrust over the last 50 years.

A Pakistani army spokesman denied that Pakistani soldiers had been involved in an unprovoked shooting, the Associated Press reported, adding that the Pakistani military had said in a statement that the Indian accusation “looks like Indian propaganda” to divert attention after the Sunday incident.

The border in Kashmir — a mountainous region that has been the cause of two wars between India and Pakistan — has been relatively calm in the past year, despite a handful of minor cease-fire violations, officials said.

Many analysts here voiced shock that the latest cross-border friction began even as the neighbors were playing a cricket tournament in India — part of a stuttering, two-year-old peace process that has eased visa requirements and boosted trade.

“This incident is serious enough to put a hold on all high-level meetings, sports and cultural exchanges,” said Lalit Mansingh, a former diplomat in New Delhi, referring to Tuesday’s development. “If the government continued the peace process, it would be out of sync with the public mood.”

The peace process, however, has produced almost no dramatic advances toward resolving the main disputes between the two countries. India accuses Pakistan of doing little to bring the perpetrators of the 2008 Mumbai terrorist attacks to justice. Pakistan, on the other hand, would like to move faster on demilitarizing the Siachen Glacier in the Himalayas — known as the world’s highest battleground — and settling a border dispute involving an estuary in western India.

“Violation of the cease-fire is bad enough, to resort to mutilating soldiers is unacceptable in any civilized society,” the chief minister of the Indian part of Kashmir, Omar Abdullah, said in a tweet. “Clearly someone up the chain of command wants to do everything to derail any dialogue between the two countries.”