(CNN) -- Two Indian soldiers died in a firefight with Pakistani army troops in the disputed Kashmir region, the Indian army said Tuesday, amid heightened tensions in the region following a deadly clash two days ago.
India said a group of Pakistani troops had crossed the Line of Control, the de facto border between India and Pakistan in the region, and entered the Indian-controlled side of the Himalayan territory.
According to the Indian military, the Pakistani troops had taken advantage of thick fog in a wooded area to intrude into the Mendhar sector of Poonch district, but were spotted by a routine Indian patrol.
After a firefight lasting about 30 minutes the Pakistani troops retreated to their side of the Line of Control, the Indian military said, leaving two Indian soldiers dead.
"This is yet another grave provocation by Pakistan Army which is being taken up sternly through official channels," a military statement said.
Gen. Asim Bajwa, a spokesman for the Pakistani military, told CNN: "We totally deny this baseless allegation."
Col. Rajesh Kalia, a spokesman for the Indian Army's northern command, told CNN: "We have lost two army soldiers in this incident and one of the bodies has been badly mutilated."
Kalia said the Indian military had not heard of any Pakistani casualties in the firefight.
Tensions flared over the weekend when a Pakistani soldier was killed in a clash between the two sides, according to the Pakistani military.
There were differing accounts of Sunday's incident.
According to the Pakistani military, Indian troops crossed the Line of Control and attacked a military post. Pakistani army troops repulsed the attack, but one Pakistani soldier was killed and another critically injured, the military said.
The Indian Defense Ministry, however, said Pakistani troops opened fire unprovoked on Indian posts in the north Uri sector of Indian-administered Kashmir. Indian troops retaliated and forced Pakistani troops to stop firing, the ministry said. It did not immediately report the number of casualties.
A statement Tuesday from the Pakistani military said: "Pakistan military officials deny (the) Indian allegation of unprovoked firing. It looks like Indian propaganda to divert the attention of the world from Sunday's raid on a Pakistani post by Indian troops, in which a Pakistani soldier was killed."
The territory under dispute lies in India's Kashmir Valley, separated from Pakistan by the 450-mile Line of Control.
The two South Asian nuclear neighbors have had a cease-fire along the de facto border since November 2003. But the cease-fire has been violated repeatedly, with both sides accusing the other of offenses.
Bilateral talks were suspended in 2008 after an attack by Pakistani militants in Mumbai, India's most populous city. The negotiations resumed last year.
The conflict dates back to 1947, after Britain relinquished control of the Indian subcontinent, giving birth to modern India and Pakistan.
Kashmir was free to accede to either nation. Maharaja Hari Singh, the ruler of the kingdom at the time, initially chose to remain independent but eventually opted to join India, thereby handing key powers to the central government in New Delhi. In exchange, India guaranteed him military protection and vowed to hold a popular vote on the issue.
The South Asian rivals have fought two full-scale wars over the territorial issue.
Islamabad has always said that majority-Muslim Kashmir should have been a part of Pakistan. A United Nations resolution adopted after the first war called for a referendum allowing the people of Kashmir to choose which country they wanted to join, but that vote for self-determination has never been held. Pakistan wants that referendum to take place.
India says that Pakistan lends support to separatist groups fighting against government control and argues that a 1972 agreement mandates a resolution to the Kashmir dispute through bilateral talks.
Shaan Khan and Habib Nasir reported from Islamabad, Pakistan, and Mukhtar Ahmad reported from Srinagar, India; CNN's Aliza Kassim also contributed to this report.