Four people killed after aircraft and helicopter collide mid-air in UK
Four people have died following a mid-air collision between a helicopter and a two-seater plane in Buckinghamshire.
They were joined in the dense woodland by paramedics, firefighters and Thames Valley Police, who said the first priority was "preservation of life".
A spokeswoman for South Central Ambulance Service said: "There have been a number of casualties at the scene, but at this stage this is all we are able to confirm.
A Notice to Airmen was previously issued to warn pilots the air field's air traffic control services would be closed during three 30-minute periods on selected days between November 7-30 due to a "staff shortage".
The crash occurred around half an hour after the latest closure was due to end.
The plane involved is a Cessna 152 with a capacity for one pilot and one passenger.
Built in 1982, it is owned by Airways Aero Associations, which is based at the air field, and had been flown for almost 14,000 hours as of May.
The aircraft suffered substantial damage to its landing gear, propeller and engine covering during a previous crash as it was taking off at Bodmin airfield in Cornwall in July 1993.
An archived report by the Air Accidents Investigation Branch shows the pilot admitted the accident was caused by his "misjudgement and lack of experience".
Waddesdon Manor, on the Rothschild family-owned estate near the Buckinghamshire crash site, described the latest incident as a "tragedy" and added it "did not happen at the manor nor have there been any casualties at Waddesdon Manor".
The manor is managed by the Rothschild Foundation, a family charitable trust, on behalf of the National Trust, who took over ownership in 1957.
RAF Halton, which is around 10 miles away, said no military aircraft were involved.
Wycombe Air Park is also known as Booker Airfield and sits around 20 miles away from the site of the crash.
It offers flight training for rookie pilots.
In May, a man was left fighting for his life after the helicopter he was travelling in with two other men crashed at the site.
A woman who lives nearby said she was out walking her dogs at the time of the collision.
"We heard a helicopter circling over head and then heard sirens," she said.
She told the Press Association she then smelled smoke, which she believes was related to the crash.
A police cordon remained in place outside the entrance to the Waddesdon estate on Friday night.
Officers were joined by members of staff from the estate.
A white tent erected inside the ground was partially visible through a high hedge from the main road, which has been reopened.