British police are investigating an attack at a London nightclub that led to a mass evacuation.
Police said Monday 12 people were treated in hospitals for burns. None of the injuries was said to be life-threatening. Two men in their 20s were in serious but stable condition.
Police say the problem at the Mangle nightclub in East London started with a dispute between two groups of people that escalated when a male suspect sprayed a "noxious substance" directly at two men.
Roads in the area were closed and a hazardous material response team rushed to the scene.
The substance hasn't yet been identified.