Breaking: Police operation underway in Sydney's inner west

A police operation has been launched in Sydney's inner west after a man was reportedly seen with a gun.Live updates, reactions and contributions from ABC readers.Riot squad officers, officers in bulletproof vests and the PolAir helicopter have responded to the incident near Williams Parade in Dulwich Hill.A witness has told the ABC that a number of ambulances arrived at the scene and another said nearby residents had been told to stay indoors.NSW Police have told nearby residents to stay indoors. (Supplied)Police said officers responded about 10:20am after reports of a stolen vehicle in a car park.Officers were told a man armed with a gun was seen inside the vehicle, before setting it alight and fleeing down Union Street.Police have described the man as Caucasian, in his 20s, about 160 centimetres tall, of a short build with shaggy hair wearing a blue T-shirt and long black pants.A helicopter seen hovering around the area. (ABC News: Berge Breiland)Light rail services have been cancelled between Dulwich Hill and Lilyfield, and a crime scene has been set up.NSW Police are asking motorists to avoid the area.