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A group of friends has been hospitalised after they were allegedly assaulted with "extreme" violence while walking down a street in Sydney's south-west.
Emergency services were called to Carpenter Street in Colyton, near Penrith, about 11.15pm yesterday over reports of the assault.
A 20-year-old man suffered serious head injuries and he and his three friends were rushed to hospital.
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Detective Inspector Steve Peroni said the injuries the 20-year-old suffered was one of the "worst categories of assault that I've seen in a long time".
"The four of them were walking down Carpenter Street … at some time they were assaulted by a group of males of unknown numbers," he said at a press conference today.
"The level of violence used is extreme.
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"The injuries indicate the use of weapons or blunt force weapons."
Peroni said some of the people involved may have left the scene, with no arrests made yet.
He added there was a particular home on the street that was a "focus of inquiry" as it is understood there was a party happening.
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Peroni could not confirm whether the alleged attack was targeted or at random but assured the community there was no further danger as far as police were aware.
Carpenter Street has since reopened after it was shut all night to allow the crime scene to be processed.
Anyone with information about the incident or was in the area and may have dashcam footage is urged to contact Crime Stoppers on 1800 333 000.
