ARLINGTON, Va. -- U.S. Park Police said two tour buses carrying teenagers from Pennsylvania collided on the George Washington Memorial Parkway, injuring a dozen of the teenagers and tying up rush-hour traffic.

Southbound lanes were closed near the Chain Bridge in Arlington County at about 5:30 p.m.

Police said one bus was traveling behind the second bus. The lead bus stopped for traffic, and the second bus hit the first from behind.

The first bus was rendered disabled, and the door to the second bus had to be opened by emergency responders.

The passengers on both buses were teenagers from Pittsburgh, Penn.

Police representative Sgt. Robert Lachance said 12 teenagers suffered minor neck and back injuries, and seven of them were being treated at a hospital. He said their injuries appear to be non-life-threatening.

Lachance says the accident happened south of Route 123 and that traffic in the area was tied up for hours.

Anyone with information about the crash should call the U.S. Park Police Communications at 202-619-7105.

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