Austin Santoro Credit: Kittery Police Department

Following Austin Santoro’s surprise guilty plea Monday, in part for sending threatening emails purporting to be from Portsmouth, New Hampshire, Police Chief Robert Merner, federal prosecutors filed new information detailing the case against the York man.

Santoro, 23, of 122 Cider Hill Road, was found competent by Judge D. Brock Hornsby during a Dec. 17 competency hearing, court records note. He had previously filed notice that he intended to launch an insanity defense and a psychiatric evaluation was filed with the U.S. District Court of New Hampshire under seal.

[Subscribe to our free morning newsletter and get the latest headlines in your inbox]

Also filed with the court following Santoro’s Dec. 17 guilty plea is an information noting he pleaded guilty to a felony count of “transmitting threatening interstate communication.” That court filing notes that on Jan. 30, Santoro sent emails to three people, identified by initials, “in which he threatened to sexually assault them at gunpoint.”

A “prosecution version” filed with the federal court this week states that, if the case proceeded to trial, prosecutors could prove Santoro sent the email to three employees of the Portsmouth Police Department, at their police email addresses, which were “spoofed” to appear as though Merner sent them. The emails read,” Hey ladies, Hope you lock your doors tonight. I might just break in and rape you,” with further threatening language. “Thanks, Robert Merner,” the emails ended.

On the same day, according to the federal information, Santoro used the same foreign spoofing service to send five emails to employees of York County Community College, which were designed to appear as though they came from another YCCC employee. The emails had the same message the police employees received about being raped at gunpoint, court records state.

[Man accused of threatening to rape female police at gunpoint faces competency hearing]

For sending those five emails, Santoro on Monday pleaded guilty to a count of identity theft for impersonating the sender, court records show.

The federal information reports the spoofing service captured the actual IP address for the emails and a Homeland Security officer traced it to the York home Santoro shared with his parents. The officer seized a laptop and mobile phone from the home and found search history related to YCCC and Portsmouth police, federal records note.

“Santoro knew when he sent the email messages described above that they would be viewed as threats to injure others,” according to a filing by U.S. Attorney Craig Wolff.

Santoro waived indictment Monday and, court records report, he faces up to five years in prison for the threat charge, up to 20 years for the identity theft charge and a $250,000 fine for each. A sentencing date has not yet been scheduled.