Calcutta, Sept. 3: The single-biggest haul of ammunition in Calcutta was made today when police seized a truck and found 25,000 AK-47 bullets hidden inside a false ceiling in the driver’s cabin.

The truck had been parked in a lot in the port area for the past one month. An intelligence tip-off led the police to it.

Coming a day after another revelation — that the explosives used in the August 25 Mumbai blasts were routed through Calcutta — the discovery set alarm bells ringing, with senior Union home and defence ministry officials closeted with counterparts in the state home department till late evening.

“I have to admit that the city has become a transit point for militants,” city police commissioner Sujay Chakraborty said. But it had more to do with its strategic location (biggest city near the Northeast) than anything else, he explained.

Chief minister Buddhadeb Bhattacharjee, without going into the reasons for the police delay in finding out the rogue truck, said the force should be congratulated for a job well done.

Calcutta police received the central intelligence tip-off last month about a truck that had arrived from the Northeast with a huge cache of ammunition on August 6. The detective department immediately started preparing a list of every place in the city that had truck parking lots and the raids started.

The areas scanned initially were places in central Calcutta, like Burrabazar, Posta and Kolay market, where most of the state’s long-distance consignments arrive. Nothing, however, came out of the raids until today.

Around noon, the police headquarters at Lalbazar received information about a truck parked at Dhobitala on Hyde Road.

A team led by Soumen Mitra and Pijush Pandey, two top detective department officers, reached the spot in a few minutes. The chowkidar of the parking lot, Mohammed Alamgir, was questioned and he led the team to the truck.

The driver and the cleaner brought the truck last month, Alamgir said. It was laden with bamboo poles and, for the first few days, the two removed the cargo to light commercial vehicles.

For the last fortnight, however, they were nowhere to be seen. The duo’s disappearance did not strike him as suspicious, Alamgir explained, as it was not unusual for drivers and cleaners to go home and come back for another long journey.

But two persons, who “looked like Kashmiris”, appeared on the scene on August 21. They changed the number-plate (from AS-01/C-6924 to ML-07/5859). “When I asked them what they were up to, they told me that the truck’s Assam registration had lapsed and it had got a new Meghalaya registration,” Alamgir said.

The initial search did not yield anything. But the unusually low ceiling of the driver’s cabin struck the sleuths as suspicious, leading them to first tap the plywood exterior and then bust it.

Forty-eight cloth-bound parcels, olive-green in colour and neatly sewn up, and 14 smaller brown-paper packets were recovered. A few tugs and pulls at the packets yielded the bullets — all of foreign make. Some of the bigger parcels had as many as 600 bullets and the smaller 25 each.

Officials said it appeared that the plan was to take the truck to Jammu and Kashmir. The truck was waiting possibly because the militants were trying to arrange another decoy consignment, they said.

Yesterday, it appeared that the Mumbai blast explosives had been routed through the city. They came here on the Dhaka-Arunachal Pradesh-Siliguri trail, officials said, adding that the decoy used while entering the city was a consignment of fruits.

The explosives were loaded on to another truck “in central Calcutta” and that truck used computer parts as the cover, the officials added. Eight persons have been rounded up.