A man accused in the slaying of a University of Vermont student from northern Virginia pleaded not guilty Thursday.

Brian L. Rooney, 36, who was charged Wednesday in the Oct. 7 death of Michelle Gardner-Quinn of Arlington, Va., appeared briefly before Vermont District Court Judge Christina Reiss and made no statements. The pleas were entered on his behalf by defense attorney David Sleigh.

He is charged with aggravated murder and would get life without parole if convicted.

Police say Rooney killed Gardner-Quinn while sexually assaulting her. Her body was found near a gorge Oct. 13, and an autopsy determined she had been strangled and beaten. Semen found on her body matched Rooney's DNA, according to an affidavit filed in support of the charge.

Rooney, who told police he was intoxicated the night he met Gardner-Quinn, said when he was arrested on unrelated sex charges that he didn't remember what happened that night and must have blacked out, according to the affidavit released Wednesday.

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"I honestly don't know what I did that night. If I did it I deserve to die," he said, according to the affidavit.

Rooney was apparently the last person seen with Gardner-Quinn before she disappeared about 2:30 a.m. on Oct. 7 after leaving a bar in Burlington to walk back to the University of Vermont campus. A store surveillance video showed the two walking together.

Police Chief Thomas Tremblay said police don't know exactly where — or when — the killing occurred, but that it was between about 2:30 a.m. and 4:30 a.m., when Rooney returned to his parents' home in Richmond.

"We'd like to remind people that Brian is presumed innocent, and he's in fact innocent," Sleigh said after the arraignment. "We intend to test the strength of the state's case in a court of law."

Rooney said he saw the woman having trouble with her cell phone and approached her and offered his, according to the affidavit.

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