William Paterson University is investigating comments made by a sociology professor during class.

The investigation comes after a series of students shot videos showing Professor Clyde Mangarelli endorsing different conspiracy theories on topics ranging from slavery to the Holocaust.

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Video shows Mangarelli saying he does not believe the U.S. landed on the moon with the Apollo 11 mission in 1969.

Mangarelli has taught at the school since 1967, and is now under fire for sharing those biases and inaccurate history in class this past school year.

The university said in a statement, "A review of this matter is underway to determine what action may be warranted."

In 1994, Mangarelli was investigated by the university after a class handout questioned the number of Jews killed in the Holocaust. He was still able to keep his job.

Other videos show the professor stating the Irish were the first slaves in America and that Native Americans are not indigenous.