A 32-year-old Hiram motorist was killed and his passenger was injured when the car they were riding in went out of control on I-75, ran off the road and crashed into a tree, Cobb County police said.

Michael York was fatally injured about 1:30 a.m. Sunday when his yellow 2001 Ford Mustang, northbound on I-75 north of Hickory Grove Road, ran off the left side of the road, down an embankment and into the tree in the center median, police said.

A passenger in the car, Hysie Allen, 36, of Douglasville, was taken by helicopter to Grady Memorial Hospital with injuries that were not believed to be life-threatening, police said.

The Cobb police Selective Traffic Enforcement Program Unit was seeking to determine why York lost control of his car. Anyone with information on the accident should call investigators at 770-499-3987.