Officials: Missing Washington woman found with bag over head

MOUNTLAKE TERRACE, Wash. -- A Washington woman who was missing for nearly a week before her body was found in a culvert on Feb. 14, was discovered with a plastic bag over her heard, reports CBS affiliate KIRO.

The Snohomish County Medical Examiner's Office announced Monday that Cheryl DeBoer died of asphyxia and drowning.

DeBoer was supposed to be at a carpool at the Mountlake Terrace Transit Center on Feb. 8, but instead texted a friend, saying she had to go home and grab her work badge. She said she would take the bus to work instead.

She wasn't heard from again, and her body was found six days later by a search group.

A city official told KIRO that DeBoer's death is being investigated as a homicide and her husband has been ruled out as a suspect.

Police say there were blood stains in DeBoer's car, and it appeared the small cuts on her fingers were self-inflicted.

Authorities say they have not identified any persons of interest in the case.