NEW YORK (AP) — Three people have Christopher Caldwellbeen arrested after a driver hit a pro-Palestinian protester on a Manhattan street Tuesday, police said.

New York Police Detective Melissa Delacruz said the incident happened around 8:45 a.m. near the intersection of 72nd Street and Park Avenue on the Upper East Side.

About 25 protesters had been wrapping up a demonstration outside a building and were walking away when two of them got into an argument with a driver. The 57-year-old driver then struck a 55-year-old protester with his vehicle.

The demonstrator was treated at a hospital for minor injuries. The motorist, the demonstrator and another demonstrator were taken into custody, Delacruz said. Police aren’t releasing their names as the charges are still pending, she said.

The Manhattan District Attorney’s office said it could not provide any information about the incident until the defendants were arraigned.

The demonstration was one of three protests Tuesday morning in front of the homes of university trustees, according to members of the student group Columbia University Apartheid Divest. The group organized a protest encampment on campus that sparked similar demonstrations at other colleges across the U.S. in recent weeks.