Three people have died and one person has been seriously injured after a helicopter on a training flight “spiralled” out of the air and crashed in a field on the Isle of Wight.

Four people were on board the helicopter when it came down beside the A3020 near Shanklin at about 09:20 BST, Hampshire and Isle of Wight Constabulary said.

One person was airlifted to the major trauma centre at University Hospital Southampton, where they remain in a serious condition.

Operator Northumbria Helicopters said the aircraft was being used for a flying lesson and had departed from Sandown Airport about 20 minutes before it crashed.

Witness Leigh Goldsmith told the Isle of Wight County Press she was driving towards Shanklin when she saw the helicopter “spiralling” before it went out of sight and came down in a hedge.

She said she was the first on the scene and saw there were four people on board, and she believed the airbags had been activated.

Police launched a major incident at about 09:50 to co-ordinate the response to the crash, which has since been stood down.

Officers said efforts were continuing to contact and provide support for the families affected.

“At this time we are unable to provide further information about the people involved,” said a spokesperson.

“We will not be commenting on the circumstances of the incident but continue to work alongside the Air Accident Investigation Branch.”

A spokesman for Northumbria Helicopters said G-OCLV – which is listed as a Robinson R44 II aircraft – had “departed from Sandown Airport at approximately 09:00 was carrying four passengers on board including the pilot, and was undertaking a flying lesson”.

In a statement, Shanklin Town Council said it was “shocked to hear about the incident involving a pleasure flight helicopter crash landing on the outskirts of the town”.

It said there were many organised events on the island over the bank holiday weekend, including the Isle of Wight Scooter Rally, which attracted thousands of vintage scooter owners to the event at Sandown Airport.

It praised the pilot for “bringing the helicopter down” away from built up areas.

A spokeswoman for Hampshire and Isle of Wight Air Ambulance confirmed one person had been airlifted to hospital.

“We have treated and airlifted one patient to the major trauma centre, University Hospital Southampton. Our thoughts are with them, and everyone involved in today’s incident,” she said.

The Air Accidents Investigation Branch is deploying a team to the location to examine the scene.

BBC Reporter Anjana Gadgil said she could see police cars parked in the road where the accident took place.

“It’s a rural area with tall hedges lining each side of the narrow winding roads,” she said.

“The whole area has been cordoned off including the many bridleways and footpaths that crisscross the fields and hill.”

Conservative MP for the Isle of Wight East Joe Robertson has described the crash as a “tragedy” and said the community was in shock and ready to rally around the families of those involved.

He asked people to avoid the site of the crash.