A Minneapolis man has pleaded guilty to cyberstalking a woman he was pursuing romantically by using Minnesota State University Mankato's incident-reporting system.

Jeffrey C. Purdy, 29, entered his plea Monday in federal court in St. Paul and awaits sentencing on a date yet to be determined.

There is no agreement between prosecutors and the defense about what sentence Purdy will receive, said Tasha Zerna, spokeswoman for the U.S. Attorney's Office, and defense attorney Earl Gray.

Sentencing guidelines call for a prison term of 30 to 37 months, but both sides reserve the right to argue before Judge Susan Nelson for a length outside that range.

According to the indictment and other court records, Purdy threatened to injure and kidnap a former classmate at Minnesota State between Aug. 30, 2017, and Feb. 29 of this year.

Early in that time span, the woman told Mankato police that Purdy had been sending her harassing e-mails and would wait in the lobby of her building for hours. She had declined repeated romantic advances from Purdy and blocked him from her cellphone and social media accounts.

Purdy then began using the university's Silent Witness Report, an anonymous incident-reporting tool, to make several violent and sexual threats against the woman. In one he said that she would "be met with catastrophe."

Investigators traced the threats to Purdy, and in February, he admitted during an interview with investigators that he had sent all of them.

Purdy's plea was to one count of cyberstalking. Dismissed were five counts of interstate transmission of a threat to injure a person and one count of interstate transmission of a threat to kidnap the person of another.