The ex-girlfriend of an Illinois state lawmaker is accusing him of using nude photos of her to catfish men over Instagram, Politico reported Wednesday.

The former girlfriend, Kate Kelly, filed an official complaint about Republican state Rep. Nick Sauer’s alleged catfishing with the Office of the Legislative Inspector General. According to Politico, which obtained the complaint, Kelly wrote that Sauer used a fake Instagram account full of nude photos of her to “to direct message men with my photos to engage in graphic conversations of a sexual nature. The men believed they were communicating with me, and Nick shared private details of my life.”

Sauer is on the House Sexual Discrimination and Harassment Task Force and co-sponsored legislation to mandate that Illinois elected officials undergo new sexual harassment last November, according to his website. He’s now expected to resign, according to Illinois House GOP leader Jim Durkin.

“The allegations that have come forth against Representative Nick Sauer are troubling. He will be resigning from office today. We should allow the proper authorities to conduct their investigations,” Durkin said in a statement to the Chicago Tribune.

Sauer didn’t immediately reply to a VICE News request for comment. He also declined to comment on Politico’s story.

Kelly told Politico that she’d dated Sauer from 2016 to March 2018; much of their relationship was long-distance. She found out about the account only in July, she said, after a stranger contacted her over Instagram and told her that he’d been talking to someone pretending to be Kelly — for four months.

Kelly then realized that the fake Instagram had been up and running for nearly the entirety of her relationship with Sauer, according to Politico’s review of her complaint. Kelly confronted Sauer, who, she wrote, admitted to using Kelly’s nude photos to catfish “at least 8 men.”

“He was unable to provide the names and begged that I let it go,” she added.

In her complaint, Kelly reportedly said she filed a police report with the Chicago Police Department as well. Sauer, however, has not been charged with anything, according to Politico.

Acting Legislative Inspector General Julie Porter also declined to comment for Politico’s story. “I do not comment on issues relating to investigations, including whether or not a matter has been presented to me or is open,” Porter wrote in an email to Politico.