Security personnel are yet to find the opening of the tunnel found beneath the Indo-Pak border fence 300-meter inside the Indian territory.
The police have cordoned off the area around the tunnel site at Chachwal border outpost, 70km from Jammu. The tunnel, still under construction, was discovered by a farmer on Saturday.
A special BSF team from Delhi is expected to arrive on Monday to examine the tunnel which is 3 feet by 3 feet in diameter. The team will analyse factors such as the method adopted in digging the tunnel, the time taken to carry out the operation from across the border and the possibility of it being used to push infiltrators.
"The team was scheduled to arrive today but now it will reach on Monday," said an official source on Sunday.
On Sunday, digging was done 50-feet parallel to the spot where the tunnel has been detected.
IGP Jammu range Dilbagh Singh along with SSP Samba Israr Khan visited the spot where 150 police personnel have been deployed.
"We have earmarked the area in a triangular shape for carrying out digging work so as not to leave any scope for missing the tunnel's opening. The state police is coordinating with the BSF personnel in this regard," said SSP Khan.
A local farmer had observed his field caving in at three points in a straight line following which the tunnel was discovered. A pipe, perhaps used for supplying oxygen in the tunnel, was also found.
The Border Security Force (BSF) is contemplating to beef up security checks along the international border.