The 33-year-old man was shot in the leg about 2.50pm and taken to Liverpool Hospital in a serious condition.

The organiser of the Silverwater Street and Custom Motorcycle Show, Greg Hirst, said the family event, in Clyde Street, Silverwater, was normally trouble-free.

"We've never had an incident in 15 years," he said.

It is not known if the shooting was related to an explosion outside a Hells Angels clubhouse on Crystal Street, Petersham, on Wednesday.