Unlicensed explosive materials, including 1,000 kg of ammonium nitrate and raw materials used for manufacturing gelatine sticks, were seized from an explosives warehouse at suburban Thuvakudimalai near Tiruchirapalli late on Wednesday night.

District Collector Ashish Vachhani, who led the operation, said that based on a tip-off, a special police party conducted surprise raids and seized 18 bags of explosive materials.

He said police took the godown in-charge Nagaraj, 45, into custody, who confessed that the explosive materials were purchased from Vellore and the godown was owned by his uncle.

Based on his information, the police team conducted similar searches in a few places, including the house of a person -- identified only as John from adjacent Vazhavanthankottai village -- who used to buy explosives from Nagaraj. However, nothing was seized from there.