A registered sex offender from York County with a prior conviction for possession of child pornography pleaded guilty Thursday to a new federal charge of possession of child pornography.

Kevin Millette, 43, of Alfred, was arrested in the new case on Nov. 16 on a charge of transportation of child pornography, but he pleaded guilty to the lesser charge of possession in U.S. District Court in Portland as part of a plea agreement.

Millette faces a minimum of 10 years in federal prison and a maximum of 20 years when he is sentenced before Judge Nancy Torresen on May 20. Had he been convicted of the greater charge of transportation, he would have faced a minimum of 15 years in prison and maximum of 40 years.

He was already on the state’s sex offender registry for a 2010 state charge of possession of sexually explicit material of a minor under the age of 12, according to the sex offender registry website.

Millette came under investigation after the U.S. Department of Homeland Security received a tip last month from the Maine State Police that a Google email address associated with Millette’s name had been used in connection with online child pornography, according to court records.

A Homeland Security agent submitted a search warrant to Google on Nov. 10 and received information on Nov. 13 that a gmail account in Millette’s name had been used to download 11 images of child pornography to a web-based Google Drive storage space, the agent, David Fife, wrote in an affidavit.

Millette’s wife told officers that he told her that he “had had ‘this issue’ for as long as he could remember, and that he had been looking at ‘these types of pictures’ for years but that looking was all that he had done,” Fife wrote in the affidavit.

In 2010, officers found 685 images on Millette’s computer of children engaging in sex acts, court records state.