Police in north Alabama appeared to use smoke and pepper spray, or another chemical agent, to sweep protesters out of the courthouse square in Huntsville.

Video of the chaotic scene streamed by WHNT, WAFF and other media outlets showed law enforcement agents wearing gas masks and riot gear advancing on the crowd after protesters refused an order to leave the area.

Law enforcement officers appeared to deploy smoke canisters and a chemical agent. The crowd began running away and the video showed some demonstrators crying and using water to wash out their eyes.

“Do you see how they treat people,” one woman asked to the camera.

Some of the crowd then chanted expletives at police. WHNT reported that some protestors began throwing water bottles at state trooper vehicles.

The day began with a NAACP rally against police violence at a nearby park. After that rally ended, some demonstrators marched to the courthouse square chanting “no justice, no peace,” news outlets reported. Police used the tactics before 8 p.m. after demonstrators refused to leave.

Huntsville Police Chief Mark McMurray earlier in the week had defended tactics used to disperse a Monday protest. McMurray told al.com the gas was a “soft chemical agent.”