Starting about 30 yards inside the Pakistan territory, the tunnel runs between border pillars numbered 52/14 and 52/15 in the Kamalpur operational area just near the CChandigarh border observation post (BoP) and stops after another 170 metres, just 30 metres before the electrified border fencing.

``Such a major operation, which required a considerable workforce and a long time period of 40-50 days simply could not have been possible without active connivance of the Pakistani Rangers,'' inspector general of BSF, Punjab, A S Aulakh who visited the border area, toldreporters.

He said the tunnel was discovered at a time when an 11-member delegation led by him was in Lahore for the four-day bi-annual meet between BSF and Pakistan Rangers.

``As, for the first time in the history of such bi-annual meetings, we were allowed to communicate with our headquarters back home, we got to know of the tunnel discovery and immediately offered the Pakistan Rangers officers to come and see for themselves the grave development,'' Aulakh said.

Finally, last Tuesday, director general of Pakistan Rangers Maj Gen Salimullah, staff officer Col Mohd Mussadiq, Chenab rangers commandant Mohd Rafiq and wing commander (5wing) Chenab Rangers Lt Col Rafiq were shown the tunnel which started from the Pakistani territory and came 170 metres into the Indian territory, Aulakh said.

The BSF jawans, after one of them stumbled over a small camouflaged pit, removed the grass and tried to estimate the depth of the pit by inserting a long elephant grass stalk.

When the patrol team found it wasnearly five feet deep, they suspected something fishy and combed the entire area.

Soon, other similar pits were discovered revealing that these were actually airvents punctuating the tunnel. The BSF jawans even laid a naka on the night of November 18 waiting for someone to come sneaking but apparently the diggers had guessed that the border guards had caught up with their dare-devil plan, they said.

By next afternoon, the scale of the daring attempt came to light in full and it was found that the tunnel started 30 metres inside the Pak territory and was about three feet wide to start with and at places was five feet in diametre.

``Possibly, the diggers wanted to extend the tunnel by about another 100 metres underneath the border fencing from where any intruder could have walked off and mixed with the civilian population,'' senior BSF officials said, adding it could have become a permanent narco-terrorist channel for pushing men, money, explosives and drugs.

``It is not for the first time that such atunnel has been detected, though this time the tunnel was far longer and had actually crossed the international border,'' Aulakh said.

Asked whether the tunnel-digging reflected a possible slackening of vigil along the border, he said it was not possible to detect sometimes such activities due to the nature of the operational area.

``With 5-6 feet high elephant grass all around, the jawans cannot sometimes see the activities across the border despite employing all kinds of gadgets including high-power binoculars," he said.

BSF officials said their rough guess was that anywhere between six to 12 men were involved in the digging. ``But then your guess is as good as ours. We are probing everything but lot of things cannot be disclosed," they said.

Aulakh said extensive efforts were on to clear the grassas it possibly helps in keeping under wraps all movement.

The earlier tunnels were detected in the Chhanna border observation post in the same sector. While the first tunnel was detected on March 12,1997 and was 116 feet in length, the second one detected on January one last year was 182 feet long.

``Both the earlier tunnels had crossed beneath the electrified fencing and were probably meant to penetrate the fencing but this time around, the operation was literal dare-devilry with the ultras trying to have a permanent Pakistan-India narco-terrorist channel,'' said a top BSF officer.

BSF jawans also found some digging implements, a few gunny bags, used batteries (cells) of Pakistan and Chinese makes, a few clothes and improvised kerosene lamp from the tunnel. The entire tunnel has been video filmed and the Pakistan Rangers officers have been shown the site.