As divers from the Navy and the FBI joined the search for the still-missing victims of last week's Minnesota highway bridge collapse, crews pulled a car Tuesday from the wreckage dumped into the Mississippi River — but no remains were found inside.
The removal of the vehicle cleared the way for the elite Navy divers to search for bodies in the debris and murky water.
Local dive teams haven't recovered the at least eight people who are still unaccounted for and believed dead since last Wednesday's accident — in which the Interstate 35W bridge buckled and fell into the water near downtown Minneapolis — in part because of dangerously unstable wreckage.
"The U.S. Navy divers and the FBI divers are starting to remove debris that our public safety divers couldn't get to," said Minneapolis Police Capt. Mike Martin at a press conference Tuesday. "They are actively working to get in there and recover any victims we can find or any evidence we can find."
In addition to the missing, there are five known dead. Among the injured, four people were upgraded Tuesday to serious condition, leaving one still in critical condition, said Christine Hill, a spokeswoman for Hennepin County Medical Center.
The city asked residents to observe a moment of silence Tuesday evening at the minute the bridge fell, and bells at churches and City Hall were to toll immediately after.
Navy divers have been called in because of their expertise, bringing to the job lessons learned from such disasters as TWA Flight 800 and the loss of space shuttle Columbia.
The team of 15 divers and a five-member command crew arrived hours before dawn Tuesday, and several divers immediately entered the Mississippi River even though local officials encouraged them to wait until daybreak.
"Two in the morning, they dove into the water," Martin said, calling them "the best divers in the world."
"These guys make our SWAT guys look humble," he said.
The team's arrival raised hopes of speeding up the recovery operation.
"Now it's time to start going through the debris," Hennepin County Sheriff Rich Stanek said. "My folks are not salvage experts, and that's why I brought in the ones that are, the Navy."
Navy Senior Chief David Nagle said the team of divers provides greater experience and more sophisticated technology than local emergency dive squads.
"Right now we're here to assess, and we're standing by to support as requested," Nagle said.
The Navy divers will be tethered to above-ground oxygen tanks, so they can stay in the water much longer than local divers, who had been using scuba tanks. Heavy-duty equipment will allow divers to cut through steel wreckage. The Navy also has sophisticated sonar to scan for bodies.
Authorities pulled a car out of the river, but there were no bodies inside. Hennepin County Sheriff's Capt. Bill Chandler said the vehicle was removed to make room for the Navy dive operation.
Joining the Navy team was an FBI dive crew, doing forensic work for the investigation. Their tools included a small unmanned submarine equipped with a robotic arm. "It's basically crime-lab-underwater kind of work," Martin said.
Mark Phillips, owner and publisher of PS Diver Monthly, a newsletter for public safety divers in Lumberton, Texas, called Navy divers "the big guns."
A disaster "as monumental as the Minnesota bridge collapse is going to be above and beyond any local agency's capacity, regardless of where they are," he said.
Phil Newsum, executive director of the Association of Diving Contractors International, said searching a river such as the Mississippi is tough for divers. The current can knock loose and carry pieces of debris, and it stirs up mud that makes visibility nearly zero.
The Navy team will likely use its sonar to identify objects in the river that roughly match the size of a human body.
"Their imaging technology is tremendous, but once you identify where something is, you go in and you're essentially diving by Braille," Newsum said. "You're going by feel only. That's tremendously challenging."
It's also emotionally difficult work, Newsum said. "You have to get your head right before you go down there, because you're recovering a human being."
Navy divers assisted in the reclamation of historic sunken ships including the ironclad Civil War ship the Monitor. After the 1996 crash of TWA Flight 800 off Long Island, N.Y., they made more than 700 dives to recover bodies and reclaim wreckage to help the government investigation. Navy divers recovered both the flight data recorder and the cockpit voice recorder.
Teams of designers and builders are racing to meet a dawn Wednesday deadline for showing they are qualified to bid on the bridge replacement project, which the state has put on a fast track.
State transportation officials hope to award contracts next month, with the goal of having a new bridge standing at the end of 2008.
"It is doable. It is a bit fast, but this is an emergency," said Khaled Mahmoud with the Bridge Engineering Association. "And if we are ever good at anything, it's responding to emergencies."
Erecting such a bridge would ordinarily take about three years, even if the design and building phases were overlapped to save time, said Bill Cox, owner of Corman Construction Inc. in Annapolis Junction, Maryland, a road and bridge construction firm.
The state intends to write financial incentives into the contract to make the compressed schedule more likely to be met.
The Associated Press contributed to this report.