EUREKA, Calif. (AP) _ The investigation into how a woman's torso wound up floating in a channel was going nowhere until a handsome trucker walked into the sheriff's department and said he'd killed her and three other women around California.

And Wayne Adam Ford had proof: He reached into his pocket and pulled out a plastic bag containing a woman's breast.

``Until he surrendered, we didn't have sufficient evidence to file a charge,'' prosecutor Worth Dikeman said.

Ford, 36, who lived by himself in a trailer park in the nearby counterculture college town of Arcata, was arraigned Friday on a charge of first-degree murder in the case of the still-unidentified torso.

His court-appointed attorney entered an innocent plea for him. The next hearing was scheduled for Thursday. He was held on $1 million bail.

Though he initially offered details on four slayings around the state, investigators from the West have been contacting the Humboldt County Sheriff's Department to see if he could shed any light on their unsolved cases.

Among them is a task force investigating a string of killings in Spokane and Tacoma, Wash. And California investigators have asked Ford about the slayings of hitchhikers he said he picked up while hauling lumber and freight around the state.

``Everyone is taking a look at him because his method of killing matches so many cases,'' said Sgt. Glenn Johnson of the Kern County Sheriff's Department in Bakersfield.

Johnson said Ford admitted picking up a Washington state woman identified as Tina Gibbs whose nude body was found in an aqueduct near Buttonwillow in June. He said Ford also confessed to killing Lanett White, 25, of Fontana, then dumping her body near Lodi after carrying it in his truck for two or three days.

``He was clean-cut. He always kept his truck clean. Now we know why,'' said Dennis Keehn, his boss at Edeline Enterprises in Arcata, which hired Ford as a long-haul trucker in April. ``All indications were he loved his job. Then look what he was. God almighty.''

Authorities have not offered a motive, but friends and co-workers said Ford had been unhappy since his wife left him two years ago and has not let him see their young son.

The couple divorced in April. His wife and son, who turns 3 next month, live in Las Vegas, and Ford has visitation rights for one week every three months and alternating Christmases.

It was Ford's brother who talked him into turning himself in, San Bernardino sheriff's spokeswoman Linda Whittaker said.

The arrest led officials to identifying the body of Patricia Anne Tamez, a 29-year-old Victorville woman discovered dead two weeks ago in the California Aqueduct near Interstate 15 outside Hesperia. San Bernardino County officials said the body was missing a breast.

Ms. Tamez may have been working as a prostitute at truck stops, officials said. A friend, Deborah Reck, said Ms. Tamez was an upper middle class college student who dropped out because she liked to party too much and was ``really into crystal meth.''

Two other victims remain unidentified. Ford told investigators he killed and dismembered the woman whose torso was found in Ryan Slough near Eureka in October 1997.

Born in Petaluma, Ford told friends he served in the military and bounced around the West, living in Big Bear and San Clemente before moving with his wife and son to Las Vegas, where a neighbor remembered him as unremarkable.

He apparently moved to the Northern California coast, where he has family, after breaking up with his wife.

Shelley McCuen, who works graveyard shift at a fast food restaurant, said she shuddered to think that the man next door was a murderer.

She had called police two weeks ago after overhearing that two men planned to break into Ford's trailer. Police asked her to keep an eye out.

``I was trying to protect a murderer,'' she said. ``Can you believe it?''

Convenience store clerk Jeremy Fugate said when he first met Ford, he was unhappy about his wife leaving him, but was happy to learn that his young son was doing well.

``He would come in and buy his beer and cigarettes and complain about how his back was feeling,'' Fugate said. ``I would go out and have a cigarette with him and trade jokes.''

Working the late shift in the store, Fugate said he would often wonder which customers were ``right in the head and which weren't, and I always thought he was all right.''