A man has died after being struck by an ambulance transporting a patient near Sunderland, police have said.
Northumbria Police said the crash occurred on the A19, between the junctions for the A1018 and A690, shortly after 02:00 GMT.
Neither the patient nor their partner who were travelling in the ambulance were injured in the collision, while the vehicle's driver, a man in his 40s, was also not hurt and remained at the scene to assist police with their inquiries.
The North East Ambulance Service (NEAS) said the patient in the ambulance and their partner were transferred to another ambulance.
Officers from Northumbria Police's roads unit have launched an investigation into the collision.
Sgt Ben Rutherford said: "Our thoughts are firmly with the family and loved ones of the man who has tragically died following this collision.
"We will continue to support them in any way that we can at this incredibly difficult time."
Anyone with CCTV or dashcam footage of the incident itself or the moments leading up to the collision has been urged to contact the force.
Rutherford said anyone with information, no matter how insignificant it may seem, "could prove key to our investigation and help provide answers for the man's loved ones".
'Hugely tragic'
A NEAS spokesperson said: "Around [02:00] one of our ambulance crews was involved in a road traffic incident with a pedestrian on the A19 northbound, while transporting a patient and their partner to a nearby hospital.
"We dispatched a number of resources to the scene.
"The patient on board and their partner were transferred to another ambulance and taken to hospital for further treatment.
"Sadly, despite the best efforts of our crews attending, the patient injured as the result of the collision passed away at the scene.
"This is a hugely tragic incident for all involved.
"Our thoughts and condolences are with the patient's loved ones.
"We will now, of course, be working closely with the police to support their investigation."
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