The incident took place at 3.15pm this afternoon (January 10) on Gray Road.
A Northumbria Police spokesman said: “We received a report of an altercation involving three men on Gray Road, Hendon.
“It was reported that one of the males involved had assaulted the other two and then left the area.
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“Officers and emergency services attended the scene and two men, aged 35 and 33, were taken to hospital for serious but non-life-threatening injuries.
“Enquiries are ongoing and officers remain at the scene."
North East Ambulance Service (NEAs) have also confirmed that the Air Ambulance was deployed to the scene.
An NEAS spokesman said: "We were called to reports of two men injured in Gray Road in Hendon at 3.21pm this afternoon.
"We dispatched two ambulance crews and two crews from our Hazardous Area Response Team, and requested support from Great North Air Ambulance Service. Both men were taken to hospital by road for further treatment."
Photographs and video submitted to the Echo showed a section of the street has been cordoned off with police tape and “five or six” police cars have been reported as being at the scene along with a police van.
Several officers in high visibility jackets can also be seen standing guard at the incident.
Anyone with information is asked call Crimestoppers on 0800555111 or to use the Northumbria Police websites Tell us Something page, quoting reference NP-20220110-0554.