New Delhi, Nov. 22: Three Indian soldiers were killed at Machhil near the Line of Control in Kashmir and one of the bodies was "mutilated", the army said today and swore revenge.

"Three soldiers killed in action on LC in Machhal. Body of one soldier mutilated, retribution will be heavy for this cowardly act," the army's northern command wrote on Twitter.

Since September 29, at least 18 soldiers - 13 of the army and five of the BSF - have been killed in cross-border firing or raids. The tit-for-tat action is ensuring in India a steady stream of coffins draped in the Tricolour that usually reach Delhi from where they are sent to the fallen soldiers' homes.

Tuesday's was the second instance of an Indian soldier being killed and his body being mutilated since the September 29 "surgical strikes". In the last 13 years since the ceasefire on the LoC was agreed by India and Pakistan, there are four recorded instances of soldiers being beheaded and/or mutilated.

Army sources said the three soldiers were killed by militants who allegedly got covering fire from the Pakistan Army. They said the Pakistan Army had been firing across the LoC in Machhil since early this morning.

The army sources did not give details of the disfiguring of the soldier's body. On October 28, when Sepoy Mandeep Singh was killed, sources said his body was found with many marks. Some of the injuries were caused by sharp implements and cigarette butts.

When two Indian soldiers were killed and their bodies mutilated near Uri on January 2013, the BJP, then in the Opposition, had demanded a strong response. Sushma Swaraj, who was then the leader of the Opposition in the Lok Sabha, demanded 10 Pakistani heads for each Indian soldier killed.

India did respond strongly after the October 28 killing of the sepoy. In punitive fire assaults, the army claimed it had destroyed four Pakistani posts in the Keran sector. The army's statement - "that retribution will be heavy for this cowardly act" - means that the Line of Control, where ceasefire violations have been an everyday event in the last two months, is set to see an escalation in violence.

Violence on the LoC is escalating even as Pakistan army chief General Raheel Sharief's term ends this month. In India, the security establishment assesses that Sharief would like to exit in a blaze of glory and at least after ensuring that he gets his choice of successor.

Sources in the army reported that firing was intensifying in Machhil since late this afternoon. Last week, Pakistan said seven of its soldiers were killed in firing by Indian troops. Two days later General Sharief claimed at least 11 Indian soldiers had been killed.