The protest was lodged at the first ever flag meeting held here between Avtar Sigh Aulakh, Inspector General BSF, Punjab Sector and Maj Gen Salim Ullah, Director General Pakistan Rangers, Punjab province.

Meanwhile, sources in BSF said that the tunnel seemed to be the handiwork of narcotic smugglers operating in this sector. A large number of narcotic smuggling cases have been reported from this area in recent times. But the fact that it was built in one of the most heavily guarded sectors.

Aulakh, while talking to The Indian Express after the meeting, said that they had had no idea of Pakistan's intentions while meeting their Pakistani counterparts in Lahore a day before the discovery of the ``secret tunnel''. A strong protest was lodged at the flag meeting held at 2 p.m., he said.

He said that he was investigating into the negligence on the part of the BSF personnel. Aulakh refused to divulge details regarding the tunnel but said ``there is a lot to be said, just wait for a day. ''

The media was not allowed to cover the flag meeting and reporters were also denied access to the site of the tunnel.

It was the first flag meeting between the commanders from either sides in the Punjab sector. This was made possible because of the agreement signed between the two sides during the Lahore meeting on November 21.

BSF jawans patrolling the border said attemps at building such tunnels are being made only in regions elephant grass covers the border belt along the zero line. Earlier cases had escape detection due to this reason he added.