(CHICAGO) About 200 protesters returned to Michigan Avenue on Thursday, clogging traffic along Michigan Avenue’s Magnificent Mile on Christmas Eve.

The demonstration was mostly peaceful, but occasional tussles broke out with police, the Chicago Sun-Times is reporting. Police said two people were arrested and face misdemeanor charges. A 19-year-old man was charged with failure to obey police and disorderly conduct, and a 22-year-old man charged with battery and failure to obey police.

The protesters gathered at noon near the Michigan Avenue Bridge and marched back and forth on the Mag Mile and in the surrounding area for more than four hours. Organizers dubbed the event “Black Christmas.”

Recent protests have been sparked in general by anger over the treatment of black people by the Chicago Police Department, and specifically by the release of a dashcam video showing the fatal shooting of Laquan McDonald by Chicago Police Officer Jason Van Dyke on October 2014.

The city agreed to pay McDonald’s family $5 million before a lawsuit even was filed.

Van Dyke has since been charged with first-degree murder. Many were angered by how long the investigation of McDonald’s death took: 13 months. Others are convinced no charges would have been filed if the video, which the city initially fought to keep under wraps, had not been released.

Since then, allegations against other officers have come to light, more videos have been released and the U.S. Department of Justice has launched a probe of the Chicago Police Department.