SEATTLE - Authorities from several different agencies are searching for a Washington man suspected of killing a developmentally disabled woman from Longview and possibly involved in the disappearance of a Spokane man and now a man in Southern California.

The multi-state search for John Wayne Thomson, a Level 3 sex offender considered armed and dangerous by police, has gone from Spokane to Longview and is focused on Riverside County near Los Angeles. 

"Thomson is on the run, he's made statements to friends that he knows he's wanted and that he's not going back," said Rick Ells, San Bernadino County Police.

The FBI expanded its search for Thomson Thursday night after finding a car he was reportedly driving abandoned outside Los Angeles and pickup truck nearby with bloodstains inside.  Authorities confirmed the bloodstained car belongs to a missing Riverside County businessman, Chuck Headland, who was travelling from Las Vegas back to California.

"Extreme caution should be used if he's encountered," said Ells. "We want the word out to anyone that might be driving on 15 not to pick up any hitchhikers, and if he's seen, call 911."

Thirty-six-year-old Lori Hamm's body was discovered this week in Longview. Authorities say shortly after her disappearance, Thomson was seen driving Hamm's car before dumping it and stealing another.

There are also concerns about what happened to James Erhgott, 73, from Spokane.  Ehrgott disappeared on July 7th; his car showed up in Lewis County several days later.

"It's extremely important that we get him in custody, just for future public's safety," said Lewis County Prosecutor Jeremy Randolph. 

Police consider Thomson's criminal history a serious concern.  According to state documents, he began raping people when he was sixteen and dropped out of a sexual psycho therapy program.  In 2002, he was referred for civil commitment, but apparently the attorney general declined the request. A representative with the office said at the time Thomson did not fall into the category of offenders bound to repeat offend.

Authorities say Thomson is known for changing his appearance, often shaving his head. He has multiple scars on his face and body with multiple tattoos on his arms and legs.

Police say Thomson's on the run and consider him armed and dangerous. Anyone who knows his whereabouts is urged to call 911 or police immediately.