US federal agents are investigating possible connections between Islamic State (Isis) and a history professor teaching at Kent State University in Ohio and attempting to determine if he has been recruiting students for the terror network, according to an FBI source.

A joint terrorism taskforce of agents from the FBI and the Department of Homeland Security have been investigating associate history professor Julio 'Assad' Pino, who is reportedly a Muslim convert, for the last 18 months, according to the Kent State student newspaper, citing an unnamed FBI special agent. "There is no direct threat to the university," the agent said. The investigation has been confirmed by the university.

Pino denied any connection to the terror network. "I've never broken the law. I support no violence or violent organisations," he told the Akron Beacon Journal. "One man or one woman's interpretation of events can be very different from another's. As they say, 'Haters gonna hate'. Truth always prevails, and truth will prevail in this case." He suspects his outspoken comments about the Middle East may have triggered the investigation. The controversial professor once shouted "Death to Israel" during an Israeli diplomat's lecture on campus. "Rumours start, and that's the only thing I can think would draw attention from a government agency," Pino said.

Several faculty members and about 20 of the professor's students have been questioned. University president Beverly Warren is aware of the investigation, according to the agent.

"Kent State is fully cooperating with the FBI," said spokesman Eric Mansfield. "As this is an ongoing investigation, we will have no further comment. The FBI has assured Kent State that there is no threat to campus." He would not say whether or not the professor would continue to teach at the university.

The Cleveland office of the FBI also confirmed the existence of an "ongoing investigation" and that "additional information cannot be provided at this time".

The student newspaper learned of the investigation after an editor was questioned about the professor by a federal agents. Emily Mills, a college senior and editor-in-chief of the Kent Stater, the independent student newspaper, has been covering the provocative professor for years.

Agents who questioned her "said they were looking into his alleged ties to the Islamic State", Mills said. "They said it was an ongoing investigation and that they were questioning faculty and other students." She said after the interview that agents "gave me permission to publish the information".

Pino also denied any connection to Isis when he was questioned by Mills for her article. Among some of his less-popular positions on campus, Pino once praising his courage of an 18-year-old Palestinian suicide bomber. In 2009, he was interviewed by the Secret Service about his positions.