Six people were killed when two historic military planes crashed during a Dallas air show.

The cause of the collision was being investigated by national transportation officials. Three years after the crash of a bomber in Connecticut that killed seven, there is still concern about the safety of air shows. The company that owned the planes that flew in the Wings Over Dallas show has had crashes in the past.

The crash site at the Dallas Executive Airport is close to the city's downtown. There were pieces of the planes in a grassy area inside the airport.

Six people died in the crash, according to the Dallas County judge. He said authorities are still trying to identify the victims. There were no reports of injuries or deaths on the ground. There were no reports of injuries, according to Dallas Fire- Rescue.

The two planes flew close together.

I was standing there. I was in total shock and disbelief when I saw the air show. Everyone was gasping. Everyone was crying. Everyone was shocked.

The widow of a famous Air Force test pilot was at the show. She saw the burning wreck even though she didn't see the crash.

He said that it was pulverized. We knew they didn't get out, so we were just hoping.

Dallas Mayor Eric Johnson said that the crash scene was taken over by the National Transportation Safety Board. Officials said the FAA was going to investigate. The FAA said in a statement that the planes crashed after colliding.

The company that owns the planes and puts on the air show doesn't know how many people are inside, but one of the planes has a crew of four to five people. One of the planes has a single pilot. He said that the aircraft are flown by volunteers.

John Cox, a former airline captain with more than 50 years of experience, said that air shows require pilots to demonstrate their skills in low flying and other stunts. Safety Operating Systems helps smaller airlines and corporate flight services from around the world with safety planning.

Cox said the air boss is the flight controller for the event.

The air boss makes the calls and the pilots follow them. The air boss would know if a pilot had a mechanical problem.

Air shows rely on detailed plans for emergencies. It is possible for a pilot who ran into trouble to break out of formation and go to a designated area free of other planes.

During World War II, the U.S. used an enormous four-engine bomber called the B17 to attack Germany. The Kingcobra was used by the Soviets. At the end of World War II, most B-17s were scrapped and only a few remain today.

The fighter plane flew into the bomber, causing them to crash to the ground and set off a large ball of fire.

A 1995 crash of a B-26 bomber that killed five crew members was one of the previous crashes of the air force. The plane was practicing for a show. The probable cause of the 1995 crash was the failure of the pilot to maintain minimum air speed.

Three people were killed when two planes owned by the group crashed in 2001. Two people were killed when a plane owned by the group crashed.

After changing its name to avoid any association with the Civil War, the Confederate Air Force relocated to Dallas in 2014).

The website advertising the event says it is America's premier World War II Airshow. More than 40 World War II-era aircraft were to be on display at the show. There was a Saturday afternoon schedule of flying demonstrations that included the bomber parade and fighter escort.

That's right.

There was a bleed from Little Rock. AP reporters in New York City, Oklahoma City, Fargo, North Dakota, and Omaha, Nebraska, contributed to the report.