MINNEAPOLIS — The entire span of an interstate bridge suddenly broke into huge sections and collapsed into the Mississippi River during evening bumper-to-bumper traffic Wednesday, sending vehicles, tons of concrete and twisted metal crashing into the water.

At least six people died, the mayor said.

=The Interstate 35W bridge, a major link between Minneapolis and St. Paul, was in the midst of being repaired when it broke into several huge sections during rush hour.

“There were two lanes of traffic, bumper to bumper, at the point of the collapse. Those cars did go into the river,” Minneapolis Police Lt. Amelia Huffman. “At this point there is nothing to suggest that this was anything other than a structural collapse.”

The Homeland Security Department had received no indications Wednesday night that the collapse was related to an act of terrorism, department spokesman Russ Knocke said in Washington.

“At this time, there’s no indication of a nexus to terrorism,” Knocke said.

It was not clear how many people were injured. WCCO-AM reported that one body was seen being pulled from the area, covered with a blue sheet.

An estimated 50 vehicles plunged into the water and onto the land below, the Star-Tribune reported.

A burning truck and a school bus clung to one slanted slab

The bus had just crossed the bridge before it crumpled into pieces, and broadcast reports indicated the children on the bus exited out the back door.

Ramon Houge told the St. Paul Pioneer Press that he was on his way home from work on the bridge when he heard a rumbling noise, saw the ground collapse and cars go down.

Traffic was bumper to bumper and hundreds of people would have been involved, he said. He said cars backed up as best they could and he parked in a construction zone and was finally able to turn around and drive off the bridge. “It didn’t seem like it was real,” he said.

Dozens of vehicles were scattered and stacked on top of each other amid the rubble. Some people were stranded on parts of the bridge that aren’t completely in the water.

Local television stations captured video of injured people being carried up the riverbank. There was no official word on injuries, but dozens of rescue vehicles were there. Divers were also in the water.

Gregory Wernick Sr., Rockford, Ill., drove over the bridge shortly before the collapse. He stopped to get a drink nearby and heard commotion so he went back.