Officers were called to North Road, in Hetton, at around 2.30am on Saturday, May 7, following reports of a one-vehicle collision.
For reasons that are yet to be established, according to police, a black Skoda Octavia was involved in the crash and the two male occupants were taken to hospital, where they currently remain.
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Sergeant Craig Bartle, of Northumbria Police, said: “Two men are fighting for their lives as a result of this incident and we are determined to find out exactly what happened.
“I am therefore asking anybody who was travelling in that area early on Saturday morning to think about whether they saw a black Skoda, or anything that may be of interest to us.
“Please check any dashcam footage and get in touch if you believe you saw or have heard anything that can help our investigation.
"Your information, no matter how insignificant you feel it may be, could be the crucial piece of information that assists our enquiries.”
If you have any information can could help police, then you are asked to get in contact with officers via the “Tell Us Something” page on the Northumbria Police website.
Alternatively, you can call 101 and quote log number NP-20220507-0100 or email [email protected]