ANN ARBOR, Mich. (AP) _ A 17-year-old boy fired into his estranged girlfriend's bedroom window and killed her as she slept, then committed suicide, authorities said.

Jason Briggs, 17, of Manchester took his own life after shooting Greta Slusher, 13, early Tuesday in her home in Sharon Township near Ann Arbor, said Washtenaw County Sheriff's Lt. R.J. Smith.

''He shot her from where he stood outside the window,'' Smith said.

Family members found the girl's body about 7:10 a.m. They told police they heard a loud noise about four hours earlier but didn't think anything was wrong, Smith said.

Police were questioning Jason's father when a friend called and said the boy's van was parked in his driveway. State troopers found Jason dead of a single shotgun wound to the head, Smith said.

''We firmly believe it's a murder-suicide,'' the lieutenant said.

Briggs and Slusher had dated for about a year but had started having problems, Smith said.

The girl had filed an assault complaint against Jason with state police on Feb. 13, saying the boy struck her during an argument, Sebring said. The report was referred to Lenawee County prosecutors but no action had been taken, Sgt. Greg Sebring said.

''She didn't want to be with him,'' said a friend of Briggs, Ken Lane, 17. ''He was overpossessive.''