Watch: B-17 Bomber collides with another plane mid-air during air show in Texas

Two historic military planes collided and crashed to the ground Saturday during an air show in Dallas, exploding into a ball of flames and sending plumes of black smoke billowing into the sky. It was unclear how many people were on board the aircraft or if anyone on the ground was hurt.

Leah Block, a spokesperson for Commemorative Air Force, which produced the Veterans Day weekend show and owned the crashed aircraft, told ABC News she believed there were five crew members on the B-17 Flying Fortress bomber and one aboard the P-63 Kingcobra fighter plane. The Houston-based aircraft were not giving rides to paying customers at the time, she said.

Emergency crews raced to the crash scene at the Dallas Executive Airport, about 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 Boeing B-17 Flying Fortress and a Bell P-63 Kingcobra collided and crashed around 1.20 p.m., the Federal Aviation Administration said in a statement. The collision occurred during the Commemorative Air Force Wings Over Dallas show.

Also Watch| Small passenger plane crashes into lake in Tanzania, over 20 rescued