PORTLAND – A convicted sex offender who prosecutors say preyed on homeless women with substance abuse or mental health problems could return to prison for violating his probation.

Frank Lapomarda, 69, was found guilty of the probation violation Friday.

A year ago, he pleaded guilty to gross sexual assault and unlawful sexual contact in what authorities said were separate attacks. He was ordered to serve 2½ years of a 20-year prison sentence and six years of probation, but was given credit for the time he had served in jail since his arrest in 2007.

One condition of his probation was to stay away from the area near the Preble Street day shelter and soup kitchen and other agencies that serve homeless women between Forest Avenue, Franklin Arterial, Marginal Way and Congress Street.

Lapomarda was seen at the Portland post office on Forest Avenue at 7:20 p.m. on Feb. 28 by off-duty police Sgt. Robert Doherty.

Doherty, who was familiar with Lapomarda’s probation, said Lapomarda was staring at glass display cases but didn’t appear to be conducting business because the post office was closed.

Doherty followed him to the hotel on Park Avenue where he was staying and notified probation officers.

Lapomarda’s probation violation was more than simply straying over an arbitrary boundary, said Deputy District Attorney Meg Elam.

“This was in what I call ‘the zone of danger,’ which we set up because that was where he picked up his multiple rape victims,” Elam said. “He was right down the street from where the soup kitchen lets out after dinner.”

Lapomarda is classified as a medium risk to commit new offenses generally, but a high-risk sex offender because he has refused to acknowledge the seriousness of his crime or comply with recommendations of his treatment team, according to court records.

Lapomarda is scheduled to be sentenced April 15 and could be sent back to prison to serve some or all of the 17 years remaining on his sentence.

A call to his attorney was not returned by press time.

Staff Writer David Hench can be contacted at 791-6327 or at: dhench@pressherald.com