A man is in hospital with "life-threatening injuries" after an accident involving a fork-lift truck in Sunderland.
Emergency services were to called to an industrial unit on Sunderland Enterprise Park at around 8am today.
People at the scene said that a man had been injured after being trapped when a fork-lift truck overturned.
Police and the Health and Safety Executive (HSE) have launched an investigation.
A Great North Air Ambulance spokesman confirmed that they had been called to the scene and had taken the man, along with the North East Ambulance Service, by road to the Royal Victoria Infirmary in Newcastle.
He was suffering from crush injuries to his chest and abdomen, Tyne and Wear Fire and Rescue Service said.
A GNAAS spokesman said: "We were called at 8.10am and airlifted one person from the scene in the Sunderland area to the Royal Victoria Infirmary."
One worker at the scene said: "We heard someone had an accident with a fork-lift truck and had been taken to hospital.
"There were loads of police and emergency services around here this morning, it looked like a very nasty accident.
"We don't know what has happened to the man, but it looks very serious."
A Northumbria Police spokeswoman said: "Emergency services were called to Sunderland Enterprise Park in Sunderland at 8.23am on Friday, February 17, following reports of a man with injuries involving a fork-lift truck.
"The seriously injured man received medical treatment at the scene and has been taken by ambulance to the RVI.
"Police are working with the HSE to investigate the incident."
A spokesman for the HSE said: "We are aware of this incident and we are assisting the police with their enquiries at this time."
Eight firefighters from Marley Park and Sunderland Central Fire Station were called to the incident earlier today and believe the man suffered 'life threatening injuries.'
A spokesman said: "Earlier today eight fire fighters and two fire engines from Community Fire Station Sunderland Central and Marley Park attended an specialist service call at Sunderland Enterprise Park, in Sunderland.
"The alarm was caused by a man reported to be trapped following a fork-lift truck overturning.
"Crews used 20 tonne airbags and spreaders to lift the truck before securing it with chocks and blocks, releasing the casualty from under the safety cage.
"The casualty was assessed by ambulance service personnel and then conveyed to the RVI with life-threatening crush injuries to his chest and abdomen."
We will bring you more updates on this story.
* Video by Scott Miller.