LONDON (AP) — British police said Wednesday they are hunting for a suspect after several people were injured with a corrosive substance in London.

The Metropolitan Police force said nine people were hurt after a man threw the substance at a woman and two children in the Clapham area.

Detective Superintendent Alexander Castle called it a “horrific incident.”

Police said nine people had been taken to hospitals: the woman and two children; three adults who came to their assistance; and three police officers. Castle said the officers' injuries were believed to be minor. There was no immediate word on the condition of the others.

Castle said tests were underway to determine what had caused the injuries but “at this stage we believe it to be a corrosive substance.”

He said police were searching for a man who was seen fleeing the scene.