FRESNO, Calif. – Fresno State University is resisting calls to fire a history professor who posted about hanging President Trump on Twitter – a perceived threat that sparked the interest of the FBI, Secret Service and Homeland Security.

Last Saturday, German-born history professor Lars Maischak wrote that “to save American democracy, Trump must hang. The sooner and the higher, the better,” and linked to an image posted by another user headlined “The Dictators’ Club.”

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The image included a smiling Trump, with the message: “Do you know who else discredited the media? Lenin, Stalin, Hitler, Mussolini, Castro, Mao, Idi Amin, Pol Pot Hussein, Assad, Putin, ISIL/Daesh, Boko Haram … Tyrants and Fascists do it.”

The post gained little attention from Maischak’s handful of followers until Turning Point USA’s Alana Mastrangelo, Breitbart, The American Mirror and others exposed the professor’s radical perspective.

Mastrangelo also pointed out that the recent tweet was only the latest manifestation of Maischak’s apparent obsession with political assassination.

Other tweets included:

Justice = The execution of two Republicans for each deported immigrant

Has anyone started soliciting money and design drafts for a monument honoring the Trump assassin yet?

Don’t tell me to “obey the Law.” “The Law” in this country is one part Racism, one part Class Oppression, all Capitalism.

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Fresno State President Joseph Castro told The Fresno Bee that he became aware of Maischak’s online musings when he returned from a trip on Friday and immediately called federal authorities. He said he’s since had frequent contact with the FBI, Secret Service and Homeland Security.

Castro contends his primary concern “is the safety of our students and the campus community” but said university officials will not take action against the processor until they complete an investigation.

He noted that Maischak, who came to the university in 2006, is currently teaching four courses and is not a tenured professor.

Maischak initially defended his Trump tweet in an email to The Bee on Monday, alleging he was not given a chance to explain before the university took action. He said Castro is “allowing himself to be instrumentalized for a right-wing smear campaign.”

“To read this as an invitation to, or expression of intent for, murder or assassination is far-fetched,” he wrote.

The processor also took aim at Breitbart, complaining that an article calling for him to be “fired, deported or killed” prompted readers to send him hundreds of emails and thousands of tweets.

By Wednesday, Maischak was much more apologetic in a prepared statement sent in to The Bee.

“I apologize for the tone and content of my statements on Twitter,” he wrote. “With 28 followers on Twitter at the time, I never expected them to be read by anyone but a close circle of acquaintances who would know how to place them in their context.

“To treat Twitter as of no more consequence than a journal was a poor decision,” Maischak continued. “I have deleted my Twitter account, to preclude the possibility that any one reading my statements in the future would take them as encouragement to act violently or unlawfully.

“In this spirit, I am prepared to take full responsibility for my statements.”

Castro called the apology “a good first step” and said he plans to “listen to all voices” and get “a full sense of the picture” before deciding what to do with the professor.