The first crash took place on a road in Washington.
When and where was the first crash?
Shortly after 2pm on Wednesday, emergency services were called to a two-vehicle collision between a car and a truck on the A194 at Blackfell, Washington, near the A195 turn-off.
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The Great North Air Ambulance confirmed that it landed on the scene at around 2.55pm, with its paramedic and doctor team assisting and treating a patient at the scene.
How many people were injured?
Northumbria Police confirmed that a 19-year-old woman was airlifted to the Royal Victoria Infirmary in Newcastle where she was being monitored in its high dependency unit. Two other patients were taken to the Queen Elizabeth Hospital in Gateshead.
Have there been any arrests?
A Northumbria Police spokeswoman said on Thursday that a 24-year-old man had been arrested on suspicion of causing serious injury by dangerous driving and has since been released under investigation.
When did the road reopen?
Highways England confirmed the road was closed northbound between junctions two and three, with a diversion in place until shortly after 5pm.
The second crash happened on the A1231.
When and where was the second crash?
Emergency services were called shortly after 4.30pm on Wednesday, February 19, following a report of a crash involving a pedestrian and a car on the A1231 Wessington Way, Sunderland.
The helicopter from the Great North Air Ambulance landed shortly before 5pm at the scene.
Who has been injured?
The ambulance service said a teenage girl was left with “multiple serious injuries,” and the patient was airlifted to hospital from the incident.
A Northumbria Police spokesperson said: “She was transported by air ambulance to the Royal Victoria Infirmary, where she is being treated for potentially life-threatening injuries.”
When did the road reopen?
Roads were closed until midnight to allow investigations to be carried out.
Police are now appealing for witnesses and anyone with dashcam footage to call 101 quoting 770 19/02/20.