A light-rail commuter train has struck and killed a man in northeast Portland.

The Oregonian reports that a witness, Dawn Baker, said it appeared the man staggered, stumbled and tripped on the tracks Thursday morning before the train knocked him to the side.

Lt. Eric Schober of the Portland Transit Police says the man was in the crosswalk. He says authorities are unsure whether he was impaired.

The pedestrian's name has not yet been released. Schober says he was in his 50s.