NORRISTOWN, Pa. (CBS) — A Montgomery County man has pleaded guilty in connection to a January 2021 shooting at the Montgomery County Democratic Party headquarters in Norristown.

The U.S. Attorney’s Office said Wednesday 48-year-old Anthony Nero pleaded guilty to charges of sending threatening communications and cyberstalking.

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(Credit: Montgomery County District Attorney’s Office)

Court documents say Nero sent a threatening message over the internet to the MCDP stating the headquarters “should probably beef up security,” on Jan. 7, 2021. Thirteen days later, on President Joe Biden’s inauguration day, MCDP officials found the front window of its Norristown headquarters had been shot three times.

Nero admitted to Norristown police in February of sending the online threat via email and later firing into the MCDP office because he was both stressed from the pandemic and upset over the presidential election.

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Police say the email read: “Just wanted to let your offices know that you should probably beef up security. With this stolen election and Coup d’etat, violence is the only language you bloodsuckers understand. [Expletive] you and your BLM [expletive] along with ANTIFA. We WILL end this insurrection. Again, TRUMP YOU! You [expletive] traitors. Random acts of violence are difficult to investigate. Have fun.”

Authorities said the investigation confirmed two spent rounds recovered from the scene were fired from Nero’s .45 caliber pistol.

“In the midst of a politically tumultuous time in our nation, Anthony Nero sent a threatening communication and then turned those words into a violent act that could have resulted in catastrophic injury, or worse,” U.S. Attorney Jennifer Arbittier Williams said.

Nero remains in federal custody.

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“Threatening violence is bad enough, but then, Anthony Nero carried out his threat and fired multiple gunshots into the MCDP office,” Jacqueline Maguire, special agent in charge of the FBI’s Philadelphia division, said. “The FBI and our law enforcement partners are committed to investigating and holding accountable anyone engaged in such criminal behavior. Nobody should have to fear becoming the target of reckless violence.”