Two Hays residents were killed in a one-vehicle accident Sunday approximately 6 miles north of Marietta, Okla.

Mary E. Younger, 73, was driving a 2012 Toyota Camry north on Interstate 35 at approximately 2 p.m. when the vehicle left the roadway to the left and struck a guardrail, according to a report from the Oklahoma Highway Patrol.

A passenger in the vehicle, Gary J. Younger, 29, died from injuries sustained in the crash.

Mary Younger was pronounced dead at Mercy Hospital in Ardmore, Okla., from injuries.

Both were wearing seatbelts. Officials had no determination as to the cause of the accident.