bridge 'falls into river'

Part of a road bridge has collapsed into the Skagit River in the US state of Washington, officials say.

  

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Some cars managed to stop on sections of the bridge which did not fall into the river.

It happened during the evening rush hour, when the bridge was crowded with traffic.

It is not clear what caused the catastrophic collapse, but the Department of Homeland Security has ruled out terrorism.

The central section of the bridge fell into the river, hurling as many as 50 vehicles into the water.

A freight train passing under another section of the bridge was crushed.

Boats and divers rescued the injured from the water, and looked for more survivors.

A bridge crossing the Mississippi river in Minneapolis has collapsed, killing at least seven people. Photo: AP Photo/The Star Tribune, Heather Munro

Police said some vehicles were in the water after a section of the Interstate 5 highway collapsed.

The four-lane bridge is near Mount Vernon, about half way between the state's main city Seattle and the Canadian city of Vancouver.

A state trooper reported that cars and people were in the water but it is not known if there are any casualties.

The cause of the collapse is not known.

Images on Twitter showed a section of the bridge in the river with cars partly submerged. In one image a person is seen sitting on top of a car.

A reporter with the Skagit Valley Herald, who is at the scene, says a sheriff's office rescue boat has arrived and rescue crews are searching for people in the water.

The newspaper quoted a driver who said he felt a vibration as he crossed the bridge and looked in his rear-view mirror to see that a section was no longer there.