A University of Georgia graduate student was arrested Friday after authorities said he cyberstalked a Massachusetts woman for more than a year and a half and extorted her for sexually explicit images.

Gary E. Leach, 23, faces two federal charges following the FBI’s monthslong investigation and was expected to appear in court Friday.

Prosecutors said the UGA student began cyberstalking the woman in late 2019 when he obtained explicit photos and videos in exchange for money that he never paid her. He’s accused of secretly recording their private video calls and threatening to release the recordings to the woman’s family if she didn’t continue sending him sexual content on Instagram, authorities said.

Prosecutors said Leach harassed and extorted the woman even though she asked him repeatedly to stop. Officials said he reached her by setting up anonymous Instagram accounts that included nicknames for the victim and several variations of the username “u.kno_who.”

During one conversation, he reportedly asked what her father would say if he saw the video. The woman asked if he wanted money, but Leach demanded additional video calls, according to his affidavit. He also reportedly sent her a a photo of her parents’ Instagram account and threatened to send the recording to them if she didn’t continue to comply with his demands.

“While communicating with the victim, Leach allegedly indicated to her that he engaged in similar conduct with other Instagram users, telling her in one message, ‘Sweetheart, I have hundreds of vids and thousands of pictures meticulously categorized by name,’” federal prosecutors said in a news release. He also reportedly told her some of those women also had no idea they were being recorded.

The Athens man faces one count of cyberstalking and one count of extortion through interstate threats, according to charging documents. The stalking charge carries a prison sentence of up to five years, and the extortion charge carries a maximum sentence of two years, authorities said. Each charge also carries a $250,000 fine.