A former George Mason University administrator told a Fairfax County judge yesterday that he was "deeply ashamed" of videotaping himself having sex with several young men in his home and campus office and then trying to blackmail them.

Ronald J. Sinacore, 56, was associate director of the university's Office of Equity and Diversity Services until his arrest in October. A Fairfax Circuit Court jury found him guilty in June of manufacturing child pornography, possessing child pornography and extortion and recommended a sentence of 14 years in prison.

At yesterday's sentencing, Sinacore's attorney asked the court to consider sending his client to a rehabilitation center for sex offenders in lieu of more time in jail, where Sinacore has been for the past year. But Circuit Court Judge Jane Roush said she was particularly troubled by the extortion conviction and sentenced Sinacore to serve eight years in prison, suspending six of the recommended 14 years.

Roush said Sinacore will be on active probation for six years after he is released from prison. Under Virginia law, a judge can decrease but not increase a jury's sentence.

"I'm truly, deeply remorseful," Sinacore said yesterday. "I've hurt the victims, family, friends, colleagues and the community."

Fairfax police became aware of the situation when one of the young men went to a police station in September 2004 and reported that Sinacore was threatening to use tapes of sexual encounters to blackmail him for money.

The two had broken off their relationship years earlier, the man said, but Sinacore wanted it to resume. With police watching, the man met with Sinacore at the University Mall across from the George Mason campus, where Sinacore told the man that he had three videotapes of them together, according to court records. Police searched Sinacore's home on Long Boat Court in the Fairfax area, seizing computers and dozens of videotapes.

More victims emerged, including an 18-year-old man. He testified that he had one encounter with Sinacore as a 17-year-old and was unaware that it was taped. He said Sinacore demanded $10,000 to keep from showing the tape to the man's parents.

Four young men testified that they were younger than 18 when they met Sinacore through postings and chat rooms on the Internet. Sinacore was not charged with sexually molesting them, but Assistant Commonwealth's Attorney Michael P. Ben'Ary emphasized that Sinacore preyed on young men who were homosexual and afraid to tell their parents.

"They were afraid of having their sexuality exposed," Ben'Ary told the court. "Their worst nightmare would come true if they decided not to engage in sexual acts with the defendant."

In arguing for the maximum prison sentence, Ben'Ary said a risk assessment of Sinacore, the product of 18 interviews, suggests that there is a 40 percent chance that Sinacore will offend again if he does not receive treatment.

Thomas Lester, Sinacore's attorney, said he did not want to diminish the victims' suffering but said his client was a "good friend, sibling, son and a law-abiding citizen" before he began struggling with depression and other mental illness. He said Sinacore has attempted to take his life four times over the years, most recently after police charged him in October.

He said Sinacore got into a pattern of filming sexual encounters in his bedroom, whether they were with teenagers or men closer to his age.

"It speaks to a level of paranoia and self-loathing," Lester told the court. "It goes beyond a sexual perversion. There's more at work here."