At least seven died and 30 others were injured when a bus turned over on Friday on a Colombian highway, said Jose Castano, the mayor of San Luis, in Antioquia of northeast Colombia.

"We still don't know the cause of the accident," he said. The public transport bus was traveling from Medellin to Bogota, but crashed and turned over on its way. The injured have been taken to the San Luis local hospital, according to Castano.

Among the dead were the bus driver, his assistant and 5 passengers, whose identities were not immediately revealed.