A man died after mysteriously plunging 5,000ft from a plane without a parachute.

The man, in his mid-40s, plummeted from the Cessna 172 twin-seater plane over west Oxfordshire yesterday.

Air accident investigators were today examining the plane.

The man fell on to a football pitch in the village of Fifield, near Burford, just a few hundred yards from houses.

The shocked pilot managed to land safely at RAF Brize Norton.

The single-engined aircraft was travelling from France to Hinton-in-the-Hedges, near Brackley, in Northamptonshire, when the tragedy occurred at 3pm.

A CAA spokesman said the plane diverted to the RAF base when the woman pilot reported icing on the aircraft's wings and requested permission to land immediately.

The spokesman said: "Permission was given for the plane to land at RAF Brize Norton and it did so safely. "However, the pilot reported that about ten nautical miles from its destination, the passenger opened the door and jumped out.

"We have very little further information at the moment and will be continuing our investigations."

The man's body was recovered by police at 4pm after it was spotted by a Thames Valley Police helicopter crew.

Detectives have already questioned the pilot, who was said to be "extremely shocked". Police said the pilot and passenger were not related but were both British nationals.

Supt Liam Macdougall said: "The circumstances surrounding the incident are unclear and there is a full-scale investigation under way."

He said it was too early to comment on reports that the man might have deliberately jumped from the aircraft .

He said officers were "keeping an open mind" until their investigations had been completed.

An inquest into the man's death was expected to be opened today.