High alert has been sounded in the wake of the breach, which came just days before the republic day, a senior Border Security Force (BSF) officer said in a new agency report.
"During the checking of the fencing, we have detected that the fence has been cut by militants between pillar number 851 and 852, along the International Border in Abdullian Border Out Post area of Ranbir Singh border belt of Jammu district last evening, " he said.
He said that the dense fog provided them enough cover to cut nine wires on the Pakistani side and ten wires on the Indian side, which created sufficient gap to facilitate infiltration.
On detecting the security breach, the BSF, CRPF, police and army were alerted, and massive searches in the entire border belt and adjoining areas, 35 km from Jammu were conducted.
"However, we feel there are less chances of militants sneaking into this side, as there is another fence 500 metres behind the zero line, which is intact. Search operations were on in the entire border belt of RS Pura. No footprints of infiltrators have been seen, " he said.
The officer said that this is the first incident in which fence has been cut and a gap has been created for militants to infiltrate.
Following the border breach, airports across the country have been put on red alert.