WATCH: Trump Supporters Take Back Berkeley From Liberal Terror Group Antifa

Violence broke out at an anti-Trump protest in Berkeley, California, on Saturday, as anti-Trump protesters clashed with people saying they wanted to publicly and peacefully show their support for the president at a “Patriots Day” event.Trump supporters planned a rally at Berkeley on Saturday in support of the President while the far-left group Antifa planned a counter protest.

Hundreds of people were involved in the brawl, which reportedly took place near the Martin Luther King Jr. Civic Center Park.As fist fights broke out between the two sides and people threw bottles and cans over a barricade separating them, police resorted to using to an explosive device at one point in a bid to restore order. Those in the video below can be seen punching and kicking one another. Some used objects to strike and even stab opponents.

The Los Angeles Times also reported about 50 people from a pro-Trump militia group called the Oath Keepers were involved in the violence. The Oath Keepers told the Times they chose to be present at the rally to protect the Trump supporters and from Liberal Terror Group Antifa.

Stewart Rhodes, founder of the citizen militia group known as the Oath Keepers, came from Montana with about 50 people wearing security gear to protect the Trump supporters. They were joined by bikers and others who vowed to fight members of an anti-fascist group if they crossed police barricades. “I don’t mind hitting” the counter-demonstrators, whom he called “neo-Nazis,” Rhodes said. “In fact, I would kind of enjoy it.”

Berkeley Police released a message on social media earlier in the afternoon informing the public it had already confiscated numerous “prohibited items” from people at both rallies. Police banned virtually all items that could be used as a weapon, including large American flags on wooden poles.

Twenty-one people were arrested, including some on suspicion of assault with a deadly weapon, according to Officer Byron White of the Berkeley Police Department. Eleven people were injured with at least six taken to a hospital for treatment, including one stabbing victim. Saturday’s melee in Berkeley, was similar to recent clashes between left and right-wing factions in the recent past. There is almost a script to how these rallies and counter-protests go in Berkeley.