Truck Found in Reno Links 2 Week-Old Disappearances : Thousand Oaks: Westlake nurse’s vehicle is located in a casino parking lot. Girl, 16, says she was abducted by the 19-year-old man arrested there.

Police in Reno, Nev., linked a pair of week-old missing-persons cases from Ventura County on Monday when they arrested the alleged kidnaper of a 16-year-old Thousand Oaks girl and found he had been driving a missing Westlake nurse’s truck.

Ventura County detectives flew to Reno to question 19-year-old Scott Thornton about his alleged abduction of ex-girlfriend Stephanie Campbell from her home last Tuesday night and the disappearance of 34-year-old Kellie O’Sullivan nine hours earlier.

Stephanie escaped unharmed from Thornton, said Ventura County Sheriff’s Lt. Lary Reynolds.

O’Sullivan was still missing late Monday. And Thornton became a prime suspect in her disappearance when detectives found her vehicle in Reno and learned he had used it to abduct Stephanie, Reynolds said.

“We fear the worst,” Reynolds said of O’Sullivan, who disappeared last Tuesday afternoon while running errands in Westlake. “We’re hoping that something may turn up as to her whereabouts, but it’s really looking kind of bleak.”

If detectives learn that O’Sullivan has been slain, Thornton--who had been using the name Mark Scott Sarrazin--would become a prime suspect in homicide, he said.

The two cases meshed early Monday morning at the Circus Circus Hotel and Casino in Reno.

While Thornton was engrossed in a video game in the casino’s circus area, Stephanie stole away and flagged down a security guard, telling him she had been kidnaped in Ventura County, Reno Police Deputy Chief Jim Weston said.

Casino security then called Reno police.

The dispatcher sent two officers, who found Thornton on a house phone trying to get hotel staff to page the girl, Weston said.

When the officers cornered him, Thornton pulled out a .38-caliber revolver, Weston said. But when the officers drew their guns, Thornton dropped his gun, and they arrested him, Weston said.

Reno police later found O’Sullivan’s black 1991 Ford Explorer in the casino’s parking lot and confirmed that it was the vehicle used to abduct Stephanie.

Police said that Thornton abducted Stephanie from her house at about 11 p.m. last Tuesday, about nine hours after O’Sullivan and the truck were last seen at a dry cleaners in Westlake Village.

The pair had spent the past week on the road to Reno, sleeping at campgrounds along the way, Reynolds said.

Meanwhile, dozens of O’Sullivan’s family members and friends continued an intensive search Monday by helicopter and four-wheel drive vehicle through the rugged Santa Monica Mountains surrounding Westlake Village, hoping to find her alive.

“We’re still working on the premise that 2 o’clock to 11 o’clock is only nine hours, and hopefully he didn’t go very far with Kellie and she’s still alive,” said Kevin White, O’Sullivan’s boyfriend, who is coordinating the civilian search. “We’re hoping he talks. And if he doesn’t, we’re going to have to start all over again tomorrow.”

White said he rode Monday afternoon in one of two helicopters donated by friends for the search, flying over Decker Canyon, while other friends in four-wheel-drive vehicles hunted along the network of fire roads through the area for any sign of O’Sullivan.

Because O’Sullivan’s truck was equipped with four-wheel drive, “what we’re presuming is maybe he ran up there and tied her up and put her in a deserted house or something,” White said. “We’re really optimistic about this . . . It’s been almost a week, but like I say, the girl’s very strong and healthy. I’m hoping she’s still alive.”

Anyone with information on O’Sullivan’s disappearance is asked to call the Ventura County Sheriff’s Department at 494-8207.

Stephanie’s mother, Linda Campbell, said she was relieved to learn that the girl had escaped unharmed.

Campbell said the girl’s father flew to Reno to join his daughter Monday night, but that the family did not know much more about what had happened since the night of the abduction.

“Basically all we know is that she is safe,” Campbell said. “We have talked to her. She said she is fine. She wasn’t hurt. We don’t know much more than that.”

Campbell said the two teen-agers had met in early July at the Econo Lodge Motel in Thousand Oaks, where the family stayed while looking for a house after moving from Fresno.

Thornton and Stephanie went out together to movies or shopping malls, where Campbell said she always picked up her daughter afterward.

“He seemed very polite, very nice” when he came over for dinner a few times after the family got settled, Campbell said. “He always helped with the dishes type thing and said, ‘Thank you for having me over and letting me eat here.’ Stuff like that.”

The two dated for about six weeks before breaking up, Campbell said.

Then about two weeks later, Thornton suddenly appeared outside the family’s house as she and Stephanie were getting out of their car, Campbell said,

“He just came in and got her and grabbed her arm and started pulling her off. She just started screaming, ‘Mom!’ ” Campbell recalled. “I started toward them. He had a gun and he shot toward me.” Thornton then muscled the girl into a dark sport utility vehicle “like a Chevy Blazer” and sped away, Campbell said.

Lt. Reynolds said the Econo Lodge had been one of a string of places where Thornton had stayed, and that he was kicked out of a house by housemates shortly before the abduction. Thornton also had been known to camp out in a tent at Wildwood Park in Thousand Oaks, Reynolds said.

Nadine Xander, resident manager of the Econo Lodge, said she never saw Thornton in a Ford Explorer.

“He was just riding a bicycle. That’s all he had,” she said. “He stayed a few days. He was very quiet. He never caused any problems here.”

She was shocked to learn of his arrest. But she added: “In a hotel you watch for the people who cause you problems. Otherwise people are basically in and out . . . He didn’t destroy the room, and that’s all I cared about.”

Times correspondent Constance Sommer contributed to this story.