A 24-year old woman techie was killed and 14 others injured when a twin bomb blast rocked the Bangalore-Guwhati Express at the busy Chennai Central Railway station on thursday, May 1. Two persons who were travelling by the train have been detained for questioning, police said but refused to reveal further details. Police cordoned off the platform where the explosion occurred, rushed forensic experts, bomb disposal squads and sniffer dogs to look for clues and the Tamil Nadu Government transferred the investigation to its specialised wing CB-CID.