Man arrested in fatal stabbing of 69-year-old Key Peninsula woman in her home in July

TACOMA -- A 32-year-old man was arrested Monday for the fatal stabbing of a Key Peninsula woman in her home in July, the Pierce County Sheriff's Department said.

The suspect, "a known burglar," was booked in the Pierce County Jail on suspicion of first-degree murder, sheriff's detective Ed Troyer said.

The investigation started in early July after an abandoned SUV on 144th Street KPN led them to the owner, Lynn Cooper, 69, who they found dead in her Key Peninsula home. They believe she had likely been dead for days. She had been stabbed to death.

Detectives initially had no leads. But the break in the case came from a stolen vehicle and DNA evidence from a bloody knife.  A relative of the suspect found a bloody knife behind the suspect's residence and turned it in, Troyer said. DNA evidence on the knife was found to be the victim's, Troyer added.

“I can’t imagine why anyone would want to hurt her,” neighbor William Kirby said to Q13 FOX News shortly after Cooper's body was found. She "was always nice and waving hi.”

Neighbors also said this kind of crime is unusual for their isolated community.

“I think this is going to get everyone’s attention because this is really weird,” said neighbor Baron Blevins. “I’ve been out here 10 years and this is the first time something that’s happened that has been really kind of unsettling.”

Cooper’s home is believed to have been ransacked, and Troyer said it is believed the suspect was burglarizing the home when Cooper was killed. 

Troyer said the suspect was being cooperative.