BIG RAPIDS, Mich. (AP) — A science professor at a university in central Michigan who claimed sinister forces were targeting him and breaking into his home has been fired months after using racist, anti-Semitic and homophobic slurs on Twitter.

Thomas Brennan announced in a Twitter posting Saturday he’d been fired, and Ferris State University later confirmed he was dismissed last week, The Detroit News reported. The Big Rapids-based university, which put Brennan on administrative leave in November as it investigated, declined further comment.

The Torch, the university’s student-run newspaper, first reported about the tweets in November. According to the newspaper’s screenshots, one tweet said: “Covid19 is another jewish revolution.”

At the time, the university’s president, David Eisler, said the school was “shocked and outraged by these tweets.” He added the tweets were “extremely offensive and run counter to the values of our University and our commitment to diversity, equity and inclusion.”

In a statement linked to his Saturday posting, Brennan expressed remorse for the tweets. But he said they were a consequence of self-destructive behavior and migraines that stemmed from a “secret program” in which electromagnetic fields and nanotechnology were deployed against him.

“I know that many of the things I tweeted were horrible, and I don’t truly feel that way in my heart,” the statement said. “But out of spite for myself and what my world had turned into, I decided to say all the things that are some of worst things you could say.”

He added about what he described as debilitating headaches and the possibility he was delusional: “The things I said on twitter were not expressed in order to discriminate against people of different races or social categories but were uttered as a result of my disability.”