Days after the Border Security Force (BSF) detected a cross-border tunnel in Jammu's Samba sector on May 4, the security forces ramped up patrolling on the border and keep eye on the fencing and nearby areas.

According to the sources, the BSF has been tasked to initiate an anti-tunnel drive every alternate day and to closely monitor the ground along with the fencing, especially during the night patrol.

Any "abnormality" at the fencing site must be reported, the sources further said.

On May 4 evening, the BSF patrolling team found the opening of a cross-border tunnel in the area of Chak Faquira opposite the Samba sector.

The search operation was stopped due to bad light and when they started to investigate the spot on Thursday, the BSF personnel found a 150-meter-long freshly dug tunnel originating from Pakistan in which the oxygen was supplied through the 265-foot-long pipes found in the tunnel.

This was the first such structure unearthed by the BSF beneath the International Border (IB) in the past 16 months, taking the overall number to 11 in the past decade. Last year the force detected two tunnels in the Hiranagar sector of Kathua district.

The officials in the security grid said that the patrolling has been intensified to prevent the infiltration and there has been a possible "threat" on the Amarnath Yatra this year.

The annual Amarnath pilgrimage will be commencing on June 30 and the terror outfits like Hijbul Mujahidin, Al Badr, and The Resistance Front (TRF) have planned to destabilize the pilgrimage.

The security forces have been asked to intensify patrolling along the IB and Line of Control in Jammu and Kashmir to prevent the infiltration.

The sources said that tunnel might have been used by the two terrorists who attacked the CISF bus in Jammu on April 22 in which one Assistant Sub-Inspector was killed and several security personnel was injured.

Later the two terrorists were also neutralized by the security forces. (AA/IANS)