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.
A number of vehicles, including a police vehicle, were damaged after reportedly being shot at, NSW Police said in a statement.
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A man in his 50s presented to Canterbury Hospital with a gunshot wound before being transferred to the Royal Prince Alfred Hospital, NSW Ambulance said.
He is understood to remain in a critical 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, Assistant Commissioner Trent King told Today.
"I would say at least 50 shots have been fired at this stage," he said.
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.
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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, the 60-year-old man was arrested in a building on Georges River Road.
A number of firearms were seized, police said.
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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