After chasing leads for nearly a week, police investigating the disappearance of a University of Vermont student got a break when a group of hikers spotted a body in a rocky ravine.

That was only half the battle. Investigators who have identified a suspect must now come up with the evidence to link him to the death of 21-year-old Michelle Gardner-Quinn.

The suspect,Brian Rooney, lent Gardner-Quinn his cell phone during a chance encounter early Oct. 7 as she walked back to her dormitory after a night on the town with friends.

Rooney, 36, was arrested Friday on unrelated charges of sex abuse in two other Vermont counties. He was jailed without bail on those charges Saturday, pending a Monday arraignment.

In court records and interviews, a picture emerged of Rooney as a construction worker who'd had numerous scrapes with the law but no history of violent crime. His stepfather said Saturday he doesn't believe Rooney was involved in Gardner-Quinn's disappearance.

"We've got all the faith in the world in him," said Ronald Skinner, whose Richmond home was searched Tuesday as part of the investigation. "It's just unimaginable that they suspect him of something like this. He's so good with his kids, and I just know he wouldn't do this to someone else's."

Police have yet to say how Gardner-Quinn died, but were expected to release preliminary results of an autopsy Saturday.

He had been the focus of the police investigation into Gardner-Quinn's disappearance since he was recorded on a jewelry store surveillance camera with her around 2:30 a.m. Oct. 7.

Rooney was charged with sexual assault in Caladonia County, 80 miles north of Burlington, and with lewd and lascivious conduct with a child in neighboring Essex county, where he previously lived, authorities said.

He has not been charged in Gardner-Quinn's case, Police Chief Thomas Tremblay said.

"It's almost like a new investigation starts," Tremblay said. "Now, we specifically know this is a suspicious disappearance and we are conducting a kidnapping investigation."

Gardner-Quinn, a senior from Arlington, Va., was reported missing Oct. 7 after she failed to show up for a planned meeting with her parents, who had been in town for parents' weekend.

After a night of drinking, she had become separated from her friends and met Rooney — a stranger — as she walked along heavily traveled Main Street, which runs between downtown and the campus.

Tommy Lang, 21, a friend whom Gardner-Quinn called when she borrowed Rooney's phone, said Friday that nothing seemed amiss when he last spoke with her.

"She sounded completely fine and normal and exactly the way she did when she left us," said Lang, a University of Vermont senior who grew up with Gardner-Quinn in Virginia. "There wasn't anything that made me worry or made me suspicious that anything was going on."

Lang said he called the number Gardner-Quinn had used and spoke to a man.

"He really didn't tell me a whole lot. He basically said he saw her walking up the hill toward the dorms and that's about it," he said.

Gardner-Quinn hadn't been seen since, until Friday, when passers-by spotted her body near Huntington Gorge, a popular swimming hole 13 miles east of Burlington.

As night fell Friday, about two dozen Vermont State Police and Burlington police investigators and crime-scene technicians worked in and around the ravine at the Gorge. Some were seen rappelling down into the ravine in a search for clues.

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