A child was killed and eight people were injured Thursday when a bomb triggered by a militant group derailed a passenger train in the north-eastern Indian state of Assam, officials said, according to dpa. The Garib Rath Express from Assam's principal city, Guwahati, to Kolkata in West Bengal state was passing through the Kokrajhar district when the blast took place, said S Hajong, spokesman for Northeast Frontier Railways. Police claimed the National Democratic Front of Bodoland (NDFB), an outlawed rebel group fighting for an independent homeland for the Bodo people, was responsible for the blast. The Assam government had sounded a security alert across the state Wednesday and cancelled at least six long-distance trains after intelligence reports suggested the NDFB was planning to target trains, bridges, government installations, security forces and public places. There were two more blasts on rail tracks in other parts of the state hours before the Garib Rath Express derailed while the security forces recovered a powerful bomb near a bridge in the Darrang district during combing operations after the incident, the PTI and IANS news agencies reported. The engine of the Garib Rath Express bore the brunt of the blast, and it and five coaches derailed, Hajong said. A 6-year-old was killed and eight people, including two security personnel and the train driver, were injured, Hajong said. He said the casualties were low because the train was travelling at a low speed over a bridge when the blast took place. India's restive north-east is home to more than 200 ethnic groups and has been plagued by insurgency in the past half century, leaving little room for development and economic progress.