SPARTA, Wis. -

Sheriff's investigators in western Wisconsin are working to identify a woman whose body was found in a burning car.

Monroe County Sheriff's Lt. Robert Conroy said the case is being treated as a homicide. Conroy told WXOW-TV the woman's body was found in the rear of the car, although he wasn't more specific.

The burning car was discovered Sept. 18 north of Norwalk. Investigators have determined the victim was not the owner of the 1998 Pontiac Grand Prix with Minnesota license plates.

Conroy said it could be a week or more before crime lab testing to determine the woman's identity and cause of death is completed.