Two men have been killed after a plane crashed at Biggin Hill air show.
The jet crashed in the final display at the Kent airfield.
The De Havilland Vampire is said to have "fallen out of the sky" and crashed just north of the airfield.
Air show spokesman Nick Smith said: "I can think of no other way to describe it other than it just fell out of the sky.
"It was part of a display and the planes separated and we do not really know what happened then but the aircraft crashed."
James Downing, 17, from Crowborough, East Sussex, says he saw the 1950s Vampire corkscrew twice before it disappeared from sight.
He then saw a huge ball of fire leap into the air and heard a sound which he said was louder than "thunder".
He said: "As the Vampire and the Vixen turned around, the Vixen pulled away and the Vampire corkscrewed down behind the ridge. I didn't see anything until I saw the fireball go up in the air. "
He added: "A fraction of a second after it disappeared, there was a ball of fire and the sound louder than thunder."