Multiple people have died after a crash involving a police vehicle and a Volkswagen Passat on the A66 near Middlesbrough in the early hours of this morning, police have said.
The "quickly-evolving incident" has prompted a "significant" emergency response, with motorists advised to use alternative routes by Cleveland Police.
The A66 is closed in both directions between Normanby Road and Church Lane.
A "number of patients died at the scene" of the serious two-vehicle crash, North East Ambulance Service said.
Authorities are yet to confirm the number of fatalities.
A spokesperson said: "Around 3:39am this morning, a collision took place involving a police vehicle and a Volkswagen Passat on the A66 in South Bank.
"Sadly, the collision has resulted in multiple fatalities. There are significant emergency vehicles on the scene, and the road will remain closed for some time.
"The public are asked to use alternative routes.
"We are working to identify the victims and contact their families. This is a quickly-evolving incident and we ask that members of the public respectfully avoid speculation."
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A spokesperson for North East Ambulance Service said: "We were called to a serious road traffic incident involving two vehicles on the A66 at South Bank at 3.39am on 22 August.
"We sent 14 ambulance resources at the scene, including emergency ambulance crews, a specialist paramedic, our hazardous area response team and a doctor from Great North Air Ambulance Service.
"Sadly despite the best efforts of everyone attending, a number of patients died at the scene. We send condolences to all of those affected by such a tragic event and thank everyone for all they did to help."
Anna Turley, MP for the Redcar constituency where the crash took place, said: "I am deeply saddened to hear of the fatal collision on the A66 this morning.
"My thoughts are with the families and loved ones of those who have lost their lives, and with everyone affected by this terrible incident.
"Thank you to all of our emergency services, who have worked through the night responding to this devastating incident."
She added: "We would ask everyone to avoid speculating online to respect the families and the police while they do their work at this terrible time.
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(c) Sky News 2026: Multiple people have died in crash involving police vehicle on A66
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