"The impact with the pole was significant."
A man has been left with serious head injuries after crashing his e-bike into a pole in south-west Sydney last night while allegedly riding away from police.
Police attempted to stop a rider about 11pm on Saturday in Sadlier near Liverpool, it's alleged he was not wearing a helmet.
It is not known if this was the reason police chose to stop him.
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The rider, a 39-year-old man, allegedly rode away from police when he spotted them, but then hit a pole near Bungulla Street.
He suffered significant head injuries and was taken to hospital, where he underwent surgery and is now in a critical but stable condition.
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NSW Police Assistant Commissioner Brett McFadden said the officers involved hadn't been formally interviewed, meaning it was unclear the reasons for wanting stop the rider or what actions led up to the crash.
"One of the things we don't know is whether the person on the bike was known to the officers, whether there was a job they were responding to, whether there was intelligence they were responding to," he said.
"There's a lot of information that the officers have that may be able to assist with the investigation."
McFadden said he was unsure of what exact e-bike was involved in the collision, but told media it did not have pedals and was only powered by an engine.
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"I can't give you an indication of what speed, but we do know the impact with the pole was significant," he said.
A crime scene has been established and a critical incident team from an independent police force will investigate the incident.
Anyone with information about this incident is urged to contact Crime Stoppers.
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