A woman in her 80s was seriously injured after a car and ambulance were involved in a crash.
Police said the woman was a passenger in the North East Ambulance Service vehicle when it was involved in a collision with a red Seat car on the A19 near Houghton-le-Spring.
It happened on the northbound carriageway at about 8:55pm on Friday 14 April, about half a mile north of the B1404 Seaton Lane junction.
Police investigating the collision have asked witnesses to come forward.
A Northumbria Police spokesperson said: "For reasons yet to be established, a red Seat car had been in collision with a North East Ambulance Service (NEAS) vehicle."
The woman, who is described as being in her 80s, was taken to hospital with serious injuries, where she remains.
Anyone who believes they witnessed the collision, or who was in the area, has been asked to get in touch with officers.
Members of the public are asked to check any dashcam footage and contact police immediately if they see anything that may assist the ongoing investigation.
Anyone with information is asked to Northumbria Police via its website or call 101 quoting log NP-20230414-1136. Alternatively, you can email email@example.com.
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