HUNTSVILLE, Ala. (AP) — Police in north Alabama on Wednesday night used smoke and tear gas to sweep protesters out of a town 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 deployed 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.

Lt. Michael Johnson, a spokesman for the Huntsville Police Department, told WHNT that the crowd refused an order to leave. He said the crowd was breaking the law by refusing to leave and they had concerns the situation was about to turn volatile.

“We had to move forward with the tear gas, or the chemical agent as we call it,” Johnson said. “It does not cause injury. It is just not pleasant.”

Johnson told news outlets that more tha 20 people were arrested.

A wave of protests have erupted across the country after the death of George Floyd, a black man who died after a white Minneapolis police officer pressed a knee on Floyd’s neck for several minutes as Floyd pleaded that he couldnt breathe.

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. Many held “Black Lives Matter”signs and kneeled as they stood across the square from police.

Police used the shortly tactics before 8 p.m. after demonstrators refused to leave.

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

Johnson said there were no reports of injuries.

House Minority Leader Anthony Daniels spoke at the earlier peaceful rally but left with his family before the clash occured. Daniels said he had questions about why things escalated and why there was a large force of state troopers there for a crowd that did not seem large or violent.

“This is not a normal state trooper presence,” Daniels said.

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