EDMONTON -- Police say speed and alcohol were factors in an overnight car rollover on an Edmonton river valley bridge that killed one person and seriously injured two others.

Investigators say the car struck a cement barrier as it was entering the Low Level Bridge, then collided with some metal beams and flipped on its roof.

The 19-year-old male driver died at the scene.

Two male passengers suffered life-threatening injuries.

Police closed the bridge to clean up the debris and investigate.

Engineers were also brought in to inspect it for possible structural damage.