Six feared dead after military planes collide at Dallas airshow

Unclear how many were aboard aircraft at America's premier world war II airshow'

Two historical military planes collided and crashed to the ground Saturday during a Dallas airshow, federal officials said, sending plumes of black smoke billowing into the sky.

Officials didn't immediately make clear how many people were on board the aircraft or if anyone on the ground was hurt. Nonetheless, an ABC News producer - citing reporting from a colleague - said on Twitter that at least six people, all crew members, were feared dead after the crash.