Oklahoma Highway Patrol troopers say four people are dead after a crash in Ottawa County.It happened Sunday afternoon just before 4:30.Both cars were on US 60 west of County Road South 680 which is east of WyandotteTroopers say George Willis, 39, from Webb City, MO, was driving a Mustang eastbound on US 60 and crossed over the center line.The Mustang hit a Ford Ranger pickup truck head on.Troopers say Spencer Anderson, 22, from Fairland, OK, was driving the pickup truck. He was treated at a Joplin hospital and was released.An accident report indicates Drake Cobb, 14, and Syrrena Sanderson, 13, were passengers in the Mustang. They were both pronounced dead at the scene.Maryssa Sanderson, 7, is in a Missouri hospital in serious condition.The Sandersons were from Garland, TX.Samantha Delamatter, 19, was a passenger in the pickup truck. She was pronounced dead at the scene. She was from Fairland, OK.Troopers say they do not know what caused the mustang to veer left of center.