Around 40 detonators and other explosive materials were allegedly seized from a house of a former activist of People's Liberation Front of India at Sogra village in the district, police said on Thursday.
On a tip-off, police last night raided the house of Matu Singh and seized the detonators, 1.5 kg gun powder, 2.5 kg ammonium nitrate and two country-made pistols, Gumla Superintendent of Police Jatin Narwal told reporters here.
Singh, who is absconding, had broken ranks with the PLFI and allegedly indulged in extortion. He is facing at least seven cases, he said.
Following the recovery of explosives, police detained his father and younger brother.