TUCSON, Ariz. – The FBI arrested a Tucson school employee for threatening to kill U.S. Rep. Martha McSally, who represents the same district Gabrielle Giffords did when she was shot in 2011.

Investigators allege 58-year-old campus monitor Steve Martan left three threatening messages on McSally’s congressional office voicemail on May 2 and 10, warning the lawmaker to “be careful” and predicting her days “were numbered,” the Arizona Daily Star reports.

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“Martha, our sights are set on you,” one message said, according to National Public Radio. “Right between your f**king eyes.”

According to the Star:

McSally represents congressional District 2, the same district served by then-U.S. Rep. Gabrielle Giffords, who was shot and seriously wounded in an assassination attempt on Jan. 8, 2011, on the northwest side. Six people were killed and 13 wounded in the attack.

The FBI tracked the calls to Martan’s cell phone and he allegedly admitted to leaving the messages. Federal officials filed a criminal complaint on Friday in U.S. District Court in Tucson.

Martan allegedly told investigators he was “venting frustrations” with McSally’s votes in support of President Trump’s policies. He was arrested and charged with threatening to assault and murder a United States official with intent to impede the official’s duties and to retaliate against an official for the performance of duties, the Star reports.

The Tucson Unified School District placed Martan on home assignment and banned him from returning to school as school officials conduct a separate investigation.

The campus monitor was released from jail on his own recognizance and restricted to his home with the exception of court-ordered meetings. He was ordered to wear an electronic monitoring device, refrain from contacting McSally and cannot possess a firearm or weapon while on bail, according to the Star.

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McSally’s District Director C.J. Karamargin worked for Gifford when she was shot in the head during a public meeting at a Tucson Safeway in 2011, and said the new threats serve as a “wake-up call” about the direction of politics in America, NPR reports.

“We should have robust debates about the future of our country. But threats of violence cross a clear line,” he said in a prepared statement. “These threats against Congresswoman McSally should be a wake-up call for us all.”

Gifford, who has since recovered from the 2011 assassination attempt, also spoke out against the recent threats against McSally.

“No matter where you live or what job you have, you have a right to feel safe in your community, at your workplace, and in your home,” she said.

“Civil discourse and civic engagement are hallmarks of our democracy, but threats and intimidation should never be tolerated.”