A Michigan man was believed to have killed his wife and two young sons before committing suicide, police said on Saturday.

Mark Schons, 39, was found dead in his sports utility vehicle in a parking lot on Friday, two hours after police discovered the bodies of his wife and children in their home, authorities said.

Police went to the house in Novi, Michigan after a friend of the family notified authorities that the two children, Tynan, 6, and Camden, 4, did not show up for school and their mother, Jennifer Schons, 38, had missed an appointment.

Jennifer Schons had suffered multiple "sharp force injuries" and the boys had been asphyxiated with neck compressions, suggesting they were strangled, William Presley, Oakland County Medical Examiner's Office investigator, said on Saturday.

Police found Mark Schons, considered a suspect in his family's deaths, dead in his vehicle. The cause was carbon monoxide poisoning, Presley said.

Police in Novi, about 25 miles northwest of Detroit, called it an apparent homicide/suicide.

Family members and friends told police the couple was considering divorce. Local media also said they had filed for bankruptcy in December.