A Maryland man was killed and his wife seriously injured Thursday night when their car crashed on the Maine Turnpike in Arundel.

Maine State Police said the car drifted across three lanes of southbound traffic at about 6:30 p.m. and slammed into a tree beside the road.

The dead man was identified as 65-year-old Denis Bryant of Bowie, Md. He was dead at the scene, according to Maine Public Safety spokesman Stephen McCausland.

His wife, Patricia Bryant, whose age was not available, suffered multiple injuries and was flown to Maine Medical Center in Portland.

A team of six troopers investigated the crash. They suspected Bryant either fell asleep or suffered a medical condition, McCausland said.

The car was a 2006 Toyota Prius.