Rescue teams worked overnight and into Friday to find survivors trapped beneath a collapsed flyover in the eastern Indian city of Kolkata as the death toll in the accident rose to 24, dpa cited officials as saying. Police launched an investigation into the construction firm building the flyover, the local government said, and had reportedly sealed its offices. About 80 metres of the under-construction flyover crashed onto the busy Burrabazar area on Thursday burying pedestrians, cars and auto-rickshaws. Some 70 people were injured. Hundreds of personnel from National Disaster Response Force (NDRF) used drilling machines, concrete-cutters and sniffer dogs to reach people stuck under the rubble, assisted by army soldiers and policemen.