PORTLAND — A Biddeford man pleaded guilty Monday to a federal charge of cyberstalking for using the Internet to harass his former fiancee by posting sexually explicit images of her and arranging for men to seek her out for sex.

Shawn Sayer, 42, a self-employed carpenter, will get as much as 10 years in prison for the conviction if a judge determines that he’s subject to an enhanced penalty as a repeat offender. Otherwise, he will face as much as five years of incarceration.

In 2005, Sayer was convicted in state court for stalking his ex-fiancee. He has since been convicted of violating bail conditions and violating protection-from-abuse orders.

Under the conditions of his plea Monday, a charge of identity theft will be dismissed at Sayer’s sentencing, which has not yet been scheduled.

Sayer and the victim dated for about four years, until their relationship ended in 2006. According to court documents, the woman legally changed her name and moved from Maine to Louisiana in 2009 to escape his harassment.

Sayer and the woman had created sexually explicit photos and videos of themselves during their relationship, and Sayer posted them to pornography sites with the woman’s name and address attached, according to the documents.

He also created a Facebook page in her name and other online accounts that he used to post links to the sexually explicit material and pose as the woman arranging sexual encounters with men, according to the documents.

The case was investigated by the Secret Service and the Maine Sate Police Computer Crimes Unit after the woman wrote to the state Attorney General’s Office about the harassment.

Authorities said it wasn’t easy to catch Sayer because he used unsecured wireless networks to which he had no connection.

Once, when police tried to seize his computer equipment, they found he had removed the hard drives from his laptop.

Evidence was recovered from Sayer’s computer after his home was searched in July 2010.

Staff Writer Ann S. Kim can be contacted at 791-6383 or at:

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