To begin with, Sarabjeet Singh, one of the four arrested, has confessed to his role in the murder of transporter Sukhdev Singh in Cuttack, Orissa, in September 1998. He had been absconding ever since the incident. A police party has already arrived from Cuttack to question the militants.

Kulwant Sigh, a front-ranking Babbar Khalsa members like the others, had smuggled in a large quantity of Research-Developed Explosives (RDX) through the Punjab border last year and triggered a blast in a bus near Bhatinda, which resulted in a large number of casualties, police sources said.

``He's a notorious trans-border smuggler and familiar with the topography of the international border,'' an officer in the Interrogation team said.

Officials further said that along with Ranjeet Singh, Kulwant had been involved in the assassinations of several Punjab politicians. ``They were involved in some sensational killings in Punjab as well as some blasts'', City Police Commissioner J Mahapatra said, adding that the details would be divulged ``at an appropriate time''.

On Jasbir Singh, at whose house the three militants were putting up, the police said his association with the Babbar Khalsa was at least a decade old, though he was not directly involved in subversive acts.

A Punjab police official said he had sought the group's help in avenging his brother's death in a Tarn Taran land dispute 10 years ago. ``Since he owned a truck he used to help them move around,'' the officer said.

In the remand application moved late on Saturday night, the police said their remand was important since their terrorist records had been confirmed by the Punjab police. Besides, the police said, they also needed to determine their mission in Vadodara -- the application mentioned killing a VIP and targeting oil refineries -- and find out if arms and ammunition had been brought into the State. Mahapatra said the militants were also planning a bank robbery in the Chhani area. ``They were short of finances and were planning to rob a bank for sustanenace'', he said.

Official sources said that since Ranjeet and Sarabjeet were involved in extortion cases in Punjab, they could have taken up similar jobs in Gujarat as well.

The interrogation report stated that the militants had been assured of a getaway jeep and information about the cash box timings by a yet-unidentified sympathiser in the Chhani area.Meanwhile, a team of the Central Bureau of Intelligence began questioning the militants on Sunday. The Amritsar police will seek a transfer warrant for the accused after their remand here expires.