A college professor in Ohio is under investigation for supporting ISIS—but he wasn’t hiding his distasteful views.

The Federal Bureau of Investigation said Tuesday it is looking at whether Julio Pino of Kent State University supported the terrorist group and if he recruited his own students to join the Islamic State. Public posts on the history professor’s Facebook page show why the FBI might be suspicious.

Two of the cover photos posted by Pino show ISIS militants. One image appears to be a screengrab from an ISIS recruitment video, showing two masked men with guns in the back of a truck. “Keep it a secret: that’s me on the left!” Pino commented. The second image, an AFP photo from Aleppo, Syria, shows a long line of armed men marching through a desert with AK-47s raised over their heads.

Another photo shows Pino in front of the U.S. Capitol with a comment referencing 9/11.

“I told Ziad Jarah to head for the Capitol, but did he listen? No!” Pino wrote in an apparent reference to United Flight 93 hijacker Ziad Jarrah. The flight bound for Washington, D.C., crashed in Shanksville, Pennsylvania, after a passenger revolt and is believed to have been targeting the Capitol.

Pino denied supporting ISIS when asked by Kent State’s newspaper on Tuesday.

“I’ve not broken the law,” Pino said. “I don’t advocate that anyone else break the law, so I’ll stand by that statement that I fulfill my duties as an American citizen by speaking out on issues that some people find controversial, of course, but no, I have not violated any laws that I’m aware of or that anyone has informed me of. … And I ask others to respect my freedom of speech as I respect theirs.”

Pino is expected to teach two classes in the spring term, but Kent State’s president denounced his views Tuesday on Twitter.

“Prof. Pino doesn’t speak on behalf of Kent State,” Beverly Warren tweeted. “We find his comments reprehensible & counter to our core values.”

Pino has a long history of controversial remarks about Israel and terrorism. In 2011, he shouted “Death to Israel!” at a lecture by an Israeli diplomat on campus. In 2002, he praised Jerusalem suicide bomber Ayat al-Akras as a “shining star” in the campus newspaper.

Those general views aren’t grounds for prosecution, but posting pro-ISIS messages on social media can be.

In November, Terrence McNeil of nearby Akron was arrested and charged with soliciting the murder of U.S. servicemembers in ISIS’s name for re-blogging a GIF on Tumblr that featured some of their names and addresses. Prosecutors allege that McNeil broke the law because the GIF also said to “kill them wherever you find them,” even though it was created by others.

“There is some freedom of speech. If I lived in the UK I would have been arrested for the things I post on tumblr,” McNeil told a friend on Twitter before his arrest, also referencing First Amendment protections. “I don't hide my support, to my knowledge nobody in this country has been arrested simply for support.”

McNeil and two other Ohio residents have already been charged with ISIS-related crimes, though none of them have any apparent connection to Pino.