US investigators will send a team from Washington to probe the fatal crash of a North American P-51 Mustang during the National Championship Air Races at Reno.
The event has been cancelled after the aircraft - a highly-modified airframe with clipped wings, and known as the 'Galloping Ghost' - departed from the racing circuit and dived at high speed, disintegrating next to the spectator line at 16:20 on 16 September.
Organisers of the event said the accident was a "mass casualty situation". Pilot Jimmy Leeward was apparently killed, it added. At least two other individuals reportedly died in the accident, with dozens suffering various levels of injury.
Close-up photographs of the aircraft in flight moments before the crash, shown by Reno television station KOLO, appear to show that a left-hand elevator trim tab partly separated from the P-51.
The US National Transportation Safety Board said it would launch a team from Washington to the Nevada crash site on 17 September, which would include specialists in airworthiness, operations and powerplants.
NTSB board member Mark Rosekind added that the team would join regional representatives already in Reno gathering information.
Leeward had spoken of his confidence in the P-51's ability to excel during the racing. The day before the crash he told Live Airshow TV: "We're as fast as anybody in the field, or maybe even a little faster. To start with we didn't really want to show our hand until about Saturday or Sunday - we've been playing poker since last Monday and so we're ready to show a couple more cards.
"So we'll see on Friday what happens and then Saturday we'll probably go ahead and play our third ace, and on Sunday we'll do our fourth ace."