Aug 2, 2007, 1:39 GMT
Washington - A key Mississippi River bridge linking the twin cities of Minneapolis and St Paul, Minnesota collapse Wednesday at the height of the evening rush hour.
Cars apparently fell into the river, the daily St Paul Pioneer Press reported on its website. A schoolbus was reported trapped on the damaged freeway bridge, and dozens of cars were reported on the bridge at the time of the collapse.
There were at least three people declared dead at the scene, according to Kristi Rollwagen, an emergency preparedness official with the city of Minneapolis. Witness reports suggested that the death toll would rise significantly.
An emergency room doctor told broadcasters that his hospital, one of several near the scene, had seen at least one drowning fatality.
A Minnesota State Police spokeswoman said that the cause of the collapse was not immediately known, and rescue efforts were underway.
Rescue workers were using boats to try to reach some parts of the bridge, and divers were searching the river. Dark smoke wafted over part of the scene from a burning trailer truck, and firefighters were using a ladder truck to try to douse the blazing wreckage.
Mobile telephone networks were reportedly overloaded in the hours after the disaster, and authorities appealed for people to refrain from making phone calls.
The Interstate 35W bridge is a central connection between the Twin Cities. Part of the massive concrete structure over the middle of the river dropped into the water, and other sections appeared to have fallen onto railroad tracks, streets and electric power lines.
The collapse occurred about 6 pm (2200 GMT). About two hours after the bridge fell, dusk was approaching and severe thunderstorms were reported looming on the horizon, threatening to complicate rescue efforts.
US Senator Amy Klobuchar of Minnesota told the Cable News Network (CNN) from Washington that she lives less than 2 kilometres from the bridge. She said that there had been 'some construction in the area' around the steel-and-concrete bridge, which carries more than 200,000 vehicles a day.
The bridge is near the University of Minnesota campus, and the local major-league baseball team, the Minnesota Twins, started a game at the nearby Metrodome, an indoor stadium, as scheduled about an hour after the accident.
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