Dallas airshow: Pair of World War II aircraft involved in mid-air crash
Two historic military planes collided and crashed to the ground during a US air show, exploding into flames and sending plumes of black smoke billowing into the sky.
It was unclear how many people were on board the aircraft, when the incident happened on Saturday, or if anyone on the ground was hurt.
Emergency crews raced to the crash scene at the Dallas Executive Airport, about 10 miles (16 kilometers) from the city's downtown.
Live TV news footage from the scene showed people setting up orange cones around the crumpled wreckage of the bomber, which was in a grassy area.
"The videos are heartbreaking," Dallas Mayor Eric Johnson wrote on Twitter, adding that the National Transportation Safety Board had taken control of the crash scene with local police and fire services providing support.
According to a statement from the Federal Aviation Administration (FAA), the Boeing B-17 Flying Fortress and a Bell P-63 Kingcobra collided and crashed at around 1.20pm.
The collision occurred during the Commemorative Air Force Wings Over Dallas show.
The B-17, an immense four-engine bomber, was a cornerstone of US air power during World War II.
Most B-17s were scrapped at the end of World War II and only a handful remain today, largely featured at museums and air shows, according to Boeing.
Meanwhile, the Kingcobra, a US fighter plane, was used mostly by Soviet forces during the war.
Several videos posted on Twitter showed the fighter plane appearing to fly into the bomber, causing them to quickly crash to the ground and setting off a large ball of fire and smoke.
Air show safety - particularly with older military aircraft - has been a concern in the US for years.
In 2011, 11 people were killed in Reno, Nevada, when a P-51 Mustang crashed into spectators.
And in 2019, a bomber crashed in Hartford, Connecticut, killing seven people.
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Wings Over Dallas bills itself as "America’s Premier World War II Airshow" according to a website advertising the event.
The show was scheduled for November 11-13, Veterans Day weekend, and guests were to see more than 40 World War II-era aircrafts.
Its Saturday afternoon schedule involved flying demonstrations including a "bomber parade" and "fighter escorts" which featured the B-17 and P-63.
Videos of previous Wings Over Dallas events depict vintage warplanes flying low, sometimes in close formation, on simulated strafing or bombing runs. The videos also show the planes performing aerobatic stunts.
Elsewhere, officials said the FAA was launching an investigation.