Uri (Jammu and Kashmir): At least eight militants were killed when Indian soldiers fired on a group of infiltrators trying to cross over from Pakistan at the Line of Control (LoC) under the cover of Pakistani firing in Jammu and Kashmir on Tuesday, two days after a massive terror strike killed 18 soldiers in the garrison town of Uri.

"It was a major infiltration bid," an army source told IANS here.

The source said that soldiers became apprehensive about a possible infiltration bid after Pakistani troops resorted to unprovoked firing at forward Indian posts on Tuesday afternoon.

"It became clear that a cover was being provided to infiltrators from Pakistan. Indian soldiers returned the fire and kept vigil around to monitor any cross border movement. A group of armed infiltrators was immediately spotted," the source said.

"There were at least 15 who tried to cross over. Five of them were killed."

The operation was on with at least seven militants still engaged in heavy exchange of fire with Indian soldiers.

The source said the Pakistani fire from small and automatic arms targeting Indian posts in Lachhipora and Boniyar villages of the border area caused no damage to Indian posts.

Pakistan is often accused of firing at Indian posts to give cover to infiltrators.

The firing violates the 2003 ceasefire agreement between India and Pakistan along the international boundary and the LoC -- the de facto border that divides Jammu and Kashmir between the two neighbours.

Earlier, the army foiled two such attempts on September 11 and 16 in Jammu and Kashmir's Poonch and Uri sectors respectively. Four terrorists were killed in each of the operations.

The latest infiltration bid came as New Delhi and Islamabad are locked in a bitter diplomatic war of words following the Uri terror attack, which India has blamed on militants from Pakistan.

Pakistan has denied the allegations even as India claimed to have clinching evidence to support its claims.

The Indian Army has claimed to have recovered arms, ammunition and food and medicine packets with Pakistani markings during the combing operations at the military base in Uri.

India also claimed that the four attackers gunned down during the two-and-a-half hours of gun fight were foreigners.

According to the Indian Army, infiltration attempts from across the border with Pakistan have increased this year in comparison with the past three to four years.

In 2016, there have been 18 infiltration bids foiled by the Indian Army.

Some 110 militants were killed and 31 of them were gunned down near the LoC.

The army said it was a "desperate attempt" by Pakistan to create "disturbance and foment unrest" in India.