Early reports said the explosion occurred in an area bordering Dehiwela and Wellawatte.
Residents heard ambulances rushing towards the scene. The explosion was heard in a wide area around the Colombo.
Sri Lanka blast in capital
June 4, 2008 (LBO) – A blast ripped through a suburb of Sri Lanka's capital Colombo in the early morning rush hour, the military said. Military spokesman Udaya Nanayakkara said the explosion blast had gone off by a rail track.