There's no known link between last night's "terrifying" active shooter incident that locked down Sydney's Croydon Park and any terrorist or gang activity, the state's top cop says.
A 60-year-old man arrested in a major police operation in Sydney's inner west overnight was "firing indiscriminately" at people with a high-calibre rifle, police said this morning.
Streets in Croydon Park were sent into lockdown and residents were being told to stay inside after police were called to Georges River Road, near the intersection of Brighton Avenue, about 7.45pm on Sunday.
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A number of vehicles, including two police vehicles, were damaged after being shot at, Police Commissioner Mal Lanyon told 2GB this morning.
The gunman was firing "indiscriminately", Assistant Commissioner Trent King told Today.
It's believed the shooter was firing from a rooftop.
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A man in his 50s, understood to be a taxi driver, presented to Canterbury Hospital with a gunshot wound before being transferred to the Royal Prince Alfred Hospital, NSW Ambulance said.
Lanyon said the man was in a serious but stable condition after surgery, having been shot in his neck and chest.
When police arrived on the scene, the alleged gunman fired on them as well, King said.
Lanyon later confirmed that on 2GB, saying body-worn footage showed the impacts of the rounds striking nearby.
"I've seen body-worn footage where police were forced to take cover while trying to assist members of the public," he said.
One of those officers had only graduated from the academy five weeks ago, and Lanyon praised her police work during the response.
He estimated between 50 and 100 shots had been fired.
Three people presented to Campsie Police Station with minor injuries: a man and a woman in their 30s and a woman in her 50s.
Paramedics treated all three before they were taken to Canterbury Hospital.
At the scene, paramedics treated 16 people for minor injuries, including two men who were taken to the Royal Prince Alfred Hospital.
NSW Ambulance earlier said at least one man, aged in his 40s, suffered facial injuries while sheltering behind glass.
There have been no reports of police officers being injured.
About 9.30pm, tactical police entered a unit above a business on Georges River Road and arrested a 60-year-old man.
Two rifles were also seized.
The man was taken to hospital under police guard for injuries sustained during the arrest.
He remains in hospital.
"We're certainly looking at how the man got the ammunition as well as the firearm," King said.
"It's a high, high calibre rifle that he used for the incident as well."
King said it was a "horrific situation" that could have been "far worse", and he praised officers for their response.
King said no motive was yet known for the alleged shooting, but that police would speak to the arrested man at a suitable time.
A taxi driver who came under fire spoke to Today, saying he'd been driving when he heard a "bang, bang, bang".
"And then I looked next to me and I saw a couple of holes through the window. How he missed me, I don't know, I'm just shocked," he said.
"It feels like it's a movie, you know what I mean? Like, I was just going home to watch the grand final, you know?"
Police established a crime scene and roads remained closed through the night.
Tow trucks remained at the scene early this morning, with multiple vehicles still needing to be moved.
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