Security forces have launched a massive operation to track down a group of armed militants who they claim infiltrated into the Indian territory here from across the border under the garb of firing from the Pakistani side early Tuesday morning.

"A group of three to four militants have infiltrated into the state through Kanachak border after cutting the fence and under the cover of firing from Pakistan side around 0145 hours."

"A massive operation is on to track down the militants as BSF, army and police have cordoned off the entire belt and tracker dogs have been pressed into operation," BSF Deputy Inspector General S Sagwan told PTI.

He alleged that under the cover of firing, "Pakistan pushed in militants into this side of the border", adding that firing exchanges continued for over an hour till 1.45 am.

Giving details, the DIG said a group of 20 to 30 unidentified ultras took position close to the International Border (IB) on Pakistan side and opened indiscriminate firing on border patrol parties in Kanachak border area of Jammu district around 12.30 am.

The BSF troops guarding the borderline retaliated, he said adding there was no casualty on this side in the firing.

Asked whether Pakistan troops were involved in the firing, he said that their involvement cannot be ruled out and they are responsible for the security for the entire belt.

BSF has swung into action and launched a massive cordon and search operation in Kanachak border belt and adjoining areas just 15 kms from the Jammu city.