The Indian Army on Tuesday termed as "grave provocation" the death of two soldiers in an attack by Pakistani troops on a patrol party along the Line of Control (LoC) in Jammu and Kashmir's Poonch district.
Two other soldiers were wounded in strike near the town of Mendhar, about 220 kms north of Jammu.
The Pakistani troops reportedly came about 100 metres into the Indian territory and attacked the patrol party early on Tuesday morning.
The body of one of the soldiers was decapitated and was found without the head, media reports citing unnamed army sources said.
In a statement, the army said the soldiers who died were Lance Naik Hemraj and Lance Naik Sudhakar Singh.
"In a significant escalation to the continuing series of Cease Fire Violations and infiltration attempts supported by Pak Army, a group of their regular soldiers intruded across the Line of Control in the Mendhar Sect on 08 Jan 2013," the statement said.
"Pak army troops, having taken advantage of thick fog & mist in the forested area, were moving towards own posts when an alert area domination patrol spotted and engaged the intruders.
"The fire fight between Pak and own troops continued for approximately half an hour after which the intruders retreated back towards their side of Line of Control," it added
"This is yet another grave provocation by Pak Army which is being taken up sternly through official channels," the Indian army said.
Earlier, Pakistan´s Foreign Affairs Ministry on Monday had summoned India´s Deputy High Commissioner in the country to register its protest on what it called an "unprovoked attack" along its border on Sunday.
Pakistan on Sunday had said Indian troops raided a military post in the Haji Pir sector of Pakistan-occupied Kashmir, killing a soldier and injuring another.
The Indian Army however was reported as saying that it had responded to a "ceasefire violation" but did not cross the Line of Control.
Skirmishes in the disputed territory Kashmir are not uncommon between the two nuclear-armed neighbours who have fought three wars since gaining independence.