Several people were injured, including two police officers, when a mass brawl broke out on Friday evening in the city of Essen, in western Germany.

Police said more than 100 people were involved in the fight, which broke out in front of a restaurant.

Police said they did not have an exact number of injured people.

Several of the wounded were taken to hospital for treatment and police seized iron bars and knives found at the scene.

Crowded city on Friday night

The brawl drew in dozens of onlookers, Essen police said.

"We are talking about several hundred people," a police spokeswoman told public broadcaster WDR. "But it's still impossible to say who was really involved and who just happened to be in the way. After all, on a Friday night, party people are out and about."

A large contingent of officers and a helicopter were deployed, with the dispersal operation continuing into the early hours of Saturday.

It was still unclear what sparked the fight but the police believe "clan criminality" was likely behind it.

The word "clan" is usually used by German law enforcement to describe groups defined by family ties and ethnic identity.

The personal details of those involved in the brawl have yet to be determined, a police spokesman said.

Connection to earlier brawl

Authorities are also investigating whether there was a connection to a brawl in the town of Castrop-Rauxel, about 30 kilometers (19 miles) away.

Local media said the earlier fight broke out on Thursday evening involving members of two families, who attacked each other with baseball bats, knives and batons. 

Several people were injured and a 23-year-old is reported to be in critical condition.

Police said Saturday they had stepped up their presence in both Essen and Castrop-Rauxel in case of further violence.

With material from DPA news agency

Edited by: Kieran Burke

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