When James Carlson was arrested inside Columbia University’s Hamilton Hall, he was already under investigation for snatching an Israeli flag out of a man’s hand near campus and setting it on fire.

That wasn’t the first time Carlson, who has no affiliation with Columbia, had run afoul of the law. He was arrested in San Francisco in 2005 during a violent protest organized by an anarchist group, according to a senior law enforcement official.

Overall, of the 112 people arrested at Columbia on Tuesday, 32 had no affiliation with the school, or 29%, according to the mayor’s office and the New York Police Department. Out of the 170 people arrested at the City College of New York, 102 people had no ties to the school, or 60%.