Two men suffered serious injuries after the helicopter came down in fields close to Stoke Hammond, near Bletchley, Bucks.

All three are now receiving hospital treatment.

The pilot raised the alarm by walking to a nearby farm, a Thames Valley Police spokesman said.

Emergency services say they have no details yet of the flight plans or how the helicopter came down.

The helicopter is owned by Heli Air, and was based at Denham Aerodrome, near Uxbridge.

A spokesman for Heli Air said the pilot of the four-seater Robinson 44 helicopter had hired it himself to entertain his two friends on what seemed to be a "routine flight".

All three men are believed to work in the computer industry.