Officials put the latest toll at seven. Some local media said at least nine people were killed in the wreck, while other reports early Thursday citing police revised the toll down to four.

"There's no question the fatality number will go up," Minnesota Governor Tim Pawlenty told NBC, as recovery workers at the site of the wreckage resumed their search in daylight.

"We know there are a number of cars in the water we haven't been able to get to and they've been there submerged since last evening ... so the fatality number is likely to go up."

Officials said 20 to 30 people were still reported missing after the search was halted for the night at 1:00 am and recovery teams could see at least 50 vehicles submerged, television reports said.

Dozens of vehicles fell into the river or were crushed as massive sections of the eight-lane bridge on a major highway, rising 64 feet (20 meters) over the water, were sheared off during Wednesday evening rush hour in Minneapolis, Minnesota.

"The bridge started falling, cars were flying everywhere and I saw the water coming up," said Catherine Yankelevich, who was driving across the bridge when it fell.

Her car ended up in the water but she managed to roll down her window and swim to safety.

After four hours of frantic rescue efforts before night fall, the head of the fire department said the focus on Thursday would shift from search to recovery.

Jim Clack said more than 60 people were taken to hospital and it was unlikely that any more survivors would be found.

"We have moved from a rescue mode... to a recovery mode," he said.