Far-left protesters clashed with police as thousands filled the streets of London for a rally in the United Kingdom after conservative activist Tommy Robinson was arrested and jailed on Friday. He was taken into custody for allegedly refusing to hand his phone over to authorities ahead of the planned Saturday rally.

Antifa and other left-wing protesters countered the rally and became furious when police were “protecting Nazis” by making a line to block off the “Unite the Kingdom” event planned by Robinson.

The counter-protest was organized by "Stand Up to Racism." One group even became violent as they faced off with authorities blocking them from entering the area of the rally. The left-wing agitators were seen pushing and shoving officers, per the Metropolitan police.

At least four arrests took place, according to the Metropolitan Police, with two from the Stand up to Racism group as well as two from the Unite the Kingdom rally, per the Daily Mail.

UK broadcaster Adam Brooks reported that when he went to speak with the Antifa activists, he was "met with name-calling, shoulder barging & hostility from the ‘anti-fascist’ side," adding, "I simply asked why they would cover their faces. They didn’t like that."

The large march and rally took place Saturday morning after the Friday arrest of the conservative activist, similar to other patriotically themed rallies he has planned in the past.

Robinson had been slated to speak at the rally, however, he is not able to and remains in custody. Robinson was charged under Schedule Seven of the Terrorism Act 2000. Under the law, police are allowed to stop anyone going through a port "to determine whether they may be involved or concerned in the commission, preparation or instigation of acts of terrorism." He was detained on Friday in a pre-planned arraignment.

If people refuse to comply, they can be jailed for committing a criminal offense.

The rally saw thousands come out in support of Robinson, and some donned MEGA or "Make England Great Again" hats during the march, echoing the message of former President Donald Trump in the US for England. Some flew Trump flags, and one protester even wore a costume of Trump.

Some held posters in support of statements previously made by Robinson, such as "Immigration is fine with a passport," referring to the mass unvetted migration that has occurred in the UK. The poster also brought attention to what many in the country have described as "two-tier" policing, where some believe that migrants do not get the same consequences for crime as English citizens.