Hagerstown police are investigating the deaths of a mother and her two young daughters found in a car Monday as a murder-suicide.

Capt. Paul Kifer said that the investigation is ongoing, but police think that the woman, a 32-year-old Hagerstown resident, killed herself and her 6- and 18-month-old daughters. “We have to treat it as if it’s the most extreme case,” Kifer said. “We treat all undetermined deaths that way.”

The woman was in the front seat and the two small children in the back seat of a small silver car that was found in the Western Heights Middle School parking lot about 4 p.m. Monday. Police said that the car was not running. The doors and windows were closed, and Kifer said heat may have contributed to the deaths.

Kifer said the bodies bore no signs of trauma, and there were no dangerous objects that might have killed the three people in the car.

Police found a receipt in the car which indicated that the woman had purchased a DVD player from the Walmart where she was an employee before 6 a.m. Monday, Kifer said. Police are interviewing people who knew her in hopes of tracing where she went after the early-morning Walmart trip. By noon, police believe, her car was parked at the middle school, which was closed for the summer and unoccupied.

The school is on the opposite side of town from the woman’s home, Kifer said. He said that no one on the school’s staff claimed to know her.

Police are not identifying the woman or her children until they contact her immediate family. Kifer said that police reached the girls’ father, who did not live with their mother, Monday night.

The mother and her daughters lived alone, and her relatives may be in Guyana, where the woman lived before moving to the United States in 2006 or 2007, Kifer said.

She lived in other parts of the country, including West Virginia, before moving to Hagerstown. Kifer said that the two girls found dead Monday are her only known children.

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