The special task force (STF) of Bengal police on Friday recovered around 300 quintals of ammonium nitrate, a chemical which is used as an indigenous ingredient to make explosives, from a storehouse in a remote Birbhum village in Nalhati.

Sources said Friday’s recovery was made after interrogating driver Asish Keura, who was arrested while carrying 81,000 detonators in his vehicle in Birbhum’s Mohammedbazar on Thursday.

“The entire stock of the highly restricted chemical ammonium nitrate was stored illegally. The owner of the storehouse is missing. We have seized 300 quintals of those explosives and have started a probe to find out the end users,” an STF official in Calcutta said.

Senior police officers said the Union government in early 2011 restricted the use of ammonium nitrate in any fertilisers following rampant use of this chemical to make crude bombs by terrorists and other extremist groups.

“The stock is raw ammonium nitrate and it is completely banned for storage apart from industrial usages. We have to check whether the chemical had been stocked for supply to illegal stone quarries in the district or the purpose was different,” said a senior police officer.

On Thursday, the police seized Keura’s SUV with 81,000 pieces of detonators from Birbhum’s Mohammedbazar. The explosives were being ferried to Birbhum from West Champaran district in Bihar.

Sources said detonators, gelatin sticks and ammonium nitrate are used to carry out blasts in coal and stone mines to extract minerals.

STF officials, however, could not arrest the owner of the storehouse in Nalhati village as he managed to flee during the early Friday morning raid.

“Once the owner of the storehouse is arrested, we will be able to get details of the supplier and the purchasers of the restricted chemical,” said a source in STF.