PORTLAND, Ore. -- Multnomah County authorities are trying to find a convicted sex offender accused of failing to report to his parole officer.

Michael Norton, 56, has a long criminal history. Authorities said he met a mentally challenged 17-year-old boy at Pioneer Square in Portland in 1995, took him to a nearby shelter and sexually abused him. After the abuse, he was sentenced to 18 months in prison.

He has since returned to prison or jail four times because of parole violations.

He also has arrests and convictions in six states on charges including prostitution, larceny, possession of marijuana and failure to register as a sex offender.

Police said Norton's last known area of residence was in Old Town in Portland. When questioned, several people in Old Town said they recognized the face.

"I've seen him before," said Michael Longatino, who recognized Norton's mug shot. "I mean, I haven't seen him recently, but I have seen him before."

Norton is described as white, 6 feet 1 inch tall and 150 pounds with brown hair and brown eyes.

Anyone with information on Norton's location is asked to call local law enforcement.

Wanted Sex Offender Last Seen In Old Town