(CBS/AP) RENTON, Wash. - A multi-state manhunt is underway for a man accused of killing his grandparents who picked him up after his release from a Washington state prison. The victims allegedly hosted a party in the suspect's honor and offered him a room for the night.
Michael Boysen, 26, is considered extremely dangerous and may be trying to stockpile weapons, police say, according to CBS affiliate KIRO.
"I can't stress how dangerous this guy is," King County Sheriff John Urquhart said at a news conference. The sheriff said Boysen had made threats against family members and law enforcement officials, but he did not elaborate.
According to KIRO, Boysen's family members have been placed in protective custody.
"We have to catch him as soon as we can," Urquhart said.
Boysen, who goes by the name Chadd, is accused of killing his 82-year-old grandfather and his 80-year-old grandmother on Friday, the same day he was released from prison, KIRO reports. Friends and family identified the couple to TV stations as Robert R. and Norma J. Taylor.
The bodies were discovered by Boysen's mother on Saturday evening.
The sheriff said the grandparents were not shot, but he declined to provide other details about their killings, pending autopsies.
"We are at a loss as to why he killed them," Urquhart said. "We don't know what the motive is."
Boysen had been in prison since 2006 on three robbery convictions. His grandparents picked him up from a prison in Monroe, north of Seattle, and hosted a family "welcome home party" for him that night, Urquhart said.
Police said Boysen searched the Internet for gun shows in the Pacific Northwest and Nevada shortly before or after the slayings. Authorities do not believe he had a gun when he left the crime scene.
Those who knew Boysen said he was addicted to prescription drugs and went to prison for stealing from his family and local pharmacies, KIRO reports.
Boysen was scheduled to begin treatment for prescription painkillers on Monday, according to the station.
A warrant has been issued for Boysen's arrest. If he's stopped anywhere in the country, law enforcement officers will know he's a wanted man, state Corrections Department spokesman Chad Lewis said.
Boysen is white, 5-foot-10, about 170 pounds and has hazel eyes and brown hair in a photo released by police. Authorities believe he may have stolen his grandparent's car: a red 2001 Chrysler 300 with Washington license plate 046-XXU and an American flag ribbon magnet on the back.
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