One man died, another was critically ill and several members of the public, paramedics and police officers were injured after a violent fight spiralled out of control today.
A man was arrested following the incident in Harlington High Street in west London just before 4.30am today, Scotland Yard said.
One victim was pronounced dead at the scene, while a second man was left with life-threatening injuries. Three members of the public and three paramedics were also injured, although not critically.
It is thought some of the members of the public may have tried to intervene in the fight when they were attacked.
Several police officers also sustained minor injuries when they arrived to deal with the incident. It is not thought any weapons were used.
Edgar Money, owner of the Harlington Tandoori, said he believed a man had broken into a cafe in the High Street at about 4am, shortly before the fight took place.
He said: "I think that about 4am a man broke into the cafe and he made himself a cup of coffee. He was there for about half an hour -, apparently he was watching cartoons.
"Then he came out and jumped into a car."
Mr Money said he thought the man got out of the car again further down the road.
"He drove about 400 yards and then got out of the car again, that's what the police told me happened.
"That's when the fight happened. The police haven't said if the two things were linked, it's all very strange. It's chaos in the road here today."