DHAKA: At least seven people were killed and eight injured on Sunday after a gas pipeline exploded in the Bangladeshi port city of Chittagong, a police official said. The pipeline exploded in front of a five-storey building, blowing some of its walls off, Mohammad Mohsin said, citing witnesses. The injured were taken to hospital, he said, adding the death toll could rise as some were in critical condition. It was not immediately clear what caused the explosion, fire service official Amir Hossain said, adding an investigation was underway.