Four police officers were injured and eight people arrested after a protest in south London, the Metropolitan Police said.
The force added there had been clashes in Camberwell following a protest linked to “tensions within the Eritrean community”.
Footage of the incident appeared to show people wielding sticks scuffling with police, paralyzing traffic.
Police said about 50 people gathered outside a private location before violence broke out.
Police remained heavily present at the scene, near the Lighthouse Theater, on Saturday night.
In a statement, the force said eight people were arrested for offenses including violent disorder, criminal damage, possession of an offensive weapon and assaulting emergency workers.
“Four officers were injured, one of whom was taken to hospital and has now been released,” the statement continued.
The Met said all those taking part in the protest were dispersed and additional officers were called in to assist.
A dispersal order has been issued in the area until 07:00 on Sunday, which gives police the power to evict a person from the area.
Police said they worked with a group of people organizing an event at a private location on Camberwell Road.
The Met explained that those arrested were part of a group of protesters who had gathered outside the venue.