Suri, April 6: Birbhum police last night seized 1.8 lakh detonators from a mini truck bearing a Telangana registration number, a haul the cops said was the biggest in recent memory in the district that shares its borders with some Maoist-infested areas of Jharkhand.

The truck was intercepted along the Nalhati-Bahadurpur Road, which connects Birbhum with Jharkhand. The driver of the truck and his helper were arrested.

Police sources said the detonators were being taken without any valid papers to Saidpur in Bihar from Telengana. The cops have sought the help of their counterparts in Bihar to trace the man to whom the consignment of detonators was supposed to be delivered.

This is not the first time that detonators have been seized in Birbhum. In May 2014, around 800kg of high-intensity gelatine sticks and 525 detonators were recovered from the godown of a Birbhum stone-crushing unit in a haul the police had then said was the biggest in a district.

District police chief Sudheer Kumar said: "We have recovered a huge number of detonators. We are investigating all possible angles."

An officer said a police team and some CRPF jawans were patrolling the road when they stopped the truck yesterday.

"We found that the truck had a container with explosives written on. We stopped the vehicle and found it was carrying the detonators. The driver and the helper failed to explain the consignment it," the officer said.