Minneapolis, MN (CBS/AP) - Divers searched the Mississippi River on Thursday for more bodies entombed in cars trapped beneath the twisted steel and concrete slabs of a collapsed bridge. As many as 30 people were missing as the effort shifted from rescue to recovery.
The official death count stood at four Thursday morning, but Police Chief Tim Dolan said more victims were still in the water.
"We have a number of vehicles that are underneath big pieces of concrete, and we do know we have some people in those vehicles," Dolan said. "We know we do have more casualties at the scene."
The eight-lane Interstate 35W bridge, a major Minneapolis artery, was in the midst of repairs when the bridge buckled during the evening rush hour Wednesday.
Dozens of cars plummeted more than 60 feet into the Mississippi River, some falling on top one of another. A school bus sat at an angle on the concrete. At least a dozen cars were visible under water.
Divers were taking down license plate numbers for authorities to track down the vehicles' owners. Getting the vehicles out was expected to take several days and involve moving around very large, heavy pieces of bridge.
"The bridge is still shifting," Dolan said. "We're dealing with the Mississippi River. We're dealing with currents. We're going to have to do it slowly and safely."
He said police estimate that 20 to 30 people were unaccounted for, though he stressed that it was just an estimate. Fire Chief Jim Clack said Thursday that emergency work was no longer a rescue operation and had become a recovery operation.
Mark Rosenker, chairman of the National Transportation Safety Board, was in Minneapolis on Thursday. A team of 19 investigators had arrived the night before, and more were expected later in the day, he said.
One of their first tasks will be to assemble the pieces of the bridge like a jigsaw puzzle. "This will be a complex investigation," Rosenker said.
President Bush offered his condolences to victims and said the federal government would help ensure that the span is rebuilt as quickly as possible.
"We in the federal government must respond, and respond robustly, to help the people there not only recover, but to make sure that lifeline of activity, that bridge, gets rebuilt as quickly as possible," Mr. Bush said in the Rose Garden following a Cabinet meeting.
U.S. Secretary of Transportation Mary E. Peters announced Thursday that, based on Minnesota’s request, $5 million in federal relief will be available to the state to repair the I-35 bridge.
"Structurally deficient means some portions of the bridge need to be scheduled for repair or replacement. It doesn't mean that the bridge is unsafe," Peters said in an interview after touring the collapsed bridge site.
Peters said the bridge had been on a schedule for inspection every two years. She said she did not know what the specific problems were that the last inspection uncovered.
"We are going to make sure that last night’s damage and debris soon become a thing of the past. We will rebuild this bridge and repair this horrible hole in the heart of this community,” Peters said.
Relatives of some of the missing gathered in a hotel ballroom early Thursday, waiting for any news and hoping for the best.
"I've never wanted to see my brother so much in my life," said Kristi Foster, who went to an information center set up at a Holiday Inn looking for her brother Kirk. She hadn't had contact with her brother or his girlfriend, Krystle Webb, since the previous night.
Authorities initially said at least seven people had died, but Police Lt. Amelia Huffman lowered that number Thursday morning, saying, "The medical examiner's office only has four sets of remains." She said the initial reports were based on the best estimates authorities had Wednesday night.
A total of 79 people were injured, hospital officials said Thursday morning.
"It's somewhat of a miracle that it was that low," said Dr. John Hick, who led the medical response by Hennepin County Medical Center at the bridge.
As patients arrived, some were unconscious, others moaned, many had serious head and back injuries, said Dr. William Heegaard, who led the emergency department. Some were barely breathing.
"These people were severely injured," Heegaard said. "There was blood everywhere."
The Homeland Security Department said the collapse did not appear to be terrorism-related, but Hennepin County Sheriff Richard Stanek said Thursday that the cause of the collapse was still unknown.
"All indications are that it was a collapse, not an act of someone doing it," Stanek said.
He said at least a dozen submerged vehicles were visible in the water. A train had been passing beneath the roadway and it also fell, including a car carrying a chemical, polystyrene beads, that the fire chief said was not particularly hazardous.
The White House said Thursday that an inspection two years ago found structural deficiencies in the bridge. White House press secretary Tony Snow said the Interstate 35W span rated 50 on a scale of 120 for structural stability.
Jeanne Aamodt, a spokeswoman for the Minnesota Department of Transportation, said her agency was aware of the 2005 assessment. She noted that many other bridges around the country carry the same designation and declined to say what the agency had done to address the deficiencies.
On Thursday, Gov. Tim Pawlenty ordered an immediate inspection of all bridges that have a design like the one that collapsed.
The bridge had been inspected by the Minnesota Department of Transportation in 2005 and 2006 and no immediate structural problems were noted, Pawlenty said Wednesday.
"There were some minor things that needed attention," he said. "They notified us from an engineering standpoint the deck might need to be rehabilitated or replaced in 2020 or beyond."
Speaking with CBS Evening News anchor Katie Couric on Thursday, Pawlenty said there were 80,000 bridges designated as "structurally deficient," adding that inspectors of the I-35W bridge "indicated there was no need for dramatic intervention."
One Minnesota DOT plan put the timeline for replacing the bridge somewhere between 2015 and 2023, at an estimated cost of $122 million.
Road crews had been working on the bridge's joints, guardrails and lights this week with lane closures overnight on Tuesday and Wednesday.
There were 18 construction workers on the bridge at the time of the collapse, said Tom Sloan, head of the bridge division for Progressive Contractors Inc., in St. Michael. One of the workers was unaccounted for.
Sloan said his crew was placing concrete finish on the bridge for what he called a routine resurfacing project. "It was the final item on this phase of the project. Suddenly the bridge gave way," he said.
The entire span of Interstate 35W crumpled into the river below. Some injured people were carried up the riverbank, while emergency workers tended to others on the ground.
"I knew right away it was going down," survivor Bernie Toivonen told The Early Show.
"I was so lucky. I didn't get hurt," he said.
A school bus had just crossed the bridge when it collapsed. It did not go into the water, and the children were able to escape unharmed out the back door.
Christine Swift's 10-year-old daughter, Kaleigh, was on the bus, returning from a field trip to Bunker Hills in Blaine. She said her daughter called her about 6:10 p.m.
"She was screaming, 'The bridge collapsed,"' Swift said. All the kids got off the bus safely, but about 10 of the children were injured, officials said.
First lady Laura Bush planned to travel to Minneapolis on Friday to console the victims' families, Snow said.
Rep. Jim Oberstar, a Minnesota Democrat who chairs the House Transportation Committee, said he will introduce legislation Thursday to direct a minimum of $250 million to Minnesota to help replace the highway bridge. Oberstar said he would try to get the bill through the House the same day.
"I am hopeful we can get this to the Senate in time for them to pass it before the August recess begins," he said in a statement.
Oberstar said the collapse shows the need to invest in the nation's transportation infrastructure. According to his office, up to 30 percent of the nation's bridges that receive federal funding are structurally deficient to some degree.
The collapsed bridge is just blocks from the heart of Minneapolis, near tourist attractions like the new Guthrie Theater and the Stone Arch Bridge.
The steel-arched bridge, built in 1967, rose about 64 feet above the river and stretched about 1,900 feet across the water.
Copyright 2007, CBS Interactive Inc. All Rights Reserved.