The railway police on February 18 night found a hand grenade and 16 bullets from eastern India's busiest railhead Howrah station in Kolkata.
The haul by the Railway Protection Force (RPF) personnel triggered tension on the station premises.
"We have recovered a hand grenade (HE36), which is highly explosive and used mostly in warfare. The RPF also seized 16 rounds of bullets used for SLR rifles, of which 14 were live cartridges," Howrah station Superintendent of Railway Police (SRP) Shankar Singh told IANS on February 20.
He said the ammunition was recovered late February 18 night from outside the old complex of the Howrah station premises.
"We will probe how these kinds of explosives and advanced ammunition were brought to Howrah station," he said.
Additional Director General of Police (RPF) Dilip Mitra, West Bengal Criminal Investigation Department (CID) officials and several military personnel rushed to the spot.