A man has been taken to hospital with head injuries after being found on Westgate Road.
The circumstances in which the man was injured are unknown but it is believed there was an incident in Newcastle city centre.
It was reported to the North East Ambulance Service that the man had been assaulted but it has not been confirmed by police.
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The ambulance service requested help from police on Saturday evening from Central Station on Neville Street but when officers arrived the man had left.
He was found on Westgate Road and treated for his injuries at the scene before being taken to the Royal Victoria Infirmary.
A spokesman for Northumbria Police said: "The cause of his injuries are unknown."
A spokesman for the ambulance service added: "We were called at 8.37pm to a man who had been assaulted.
"We dispatched our Hazardous Area Response Team and an enhanced care paramedic crew.
"They treated the patient before transporting him to the RVI."
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