Emergency services were called to North Road in Berwick, at around 2am on Sunday, February 9 where a 39-year-old man was seriously injured on the northbound carriageway near Crispin Road.
He was taken to the RVI and has been described as “critical but stable.”
A Northumbria Police spokesperson said: “Police are keen to speak to a male and female who were believed to be at the scene and were seen to get out of a taxi. The female assisted the injured male before she and the male got back in the taxi and left the scene.
“Police are also keen to trace a female who found a mobile phone near to the Toll House and handed it to another female.”
Officers are seeking witnesses and those with dash cam footage to call 101 quoting 234 090220.