Crews have been searching for at least eight people missing and presumed killed in the Aug. 1 collapse.
MINNEAPOLIS -- Divers pulled two more bodies from the wreckage of the collapsed Mississippi River bridge Thursday, bringing the disaster's confirmed death toll to seven, more than a week after the span crumbled.
Crews have been searching for at least eight people missing and presumed killed in the Aug. 1 collapse, including a mother and her young daughter and another woman and her adult son.
One of the two bodies recovered Thursday was identified as Peter Joseph Hausmann, 47, of suburban Rosemount. Police did not identify the other victim or say whether the bodies were found together.
"Right now the first priority is notifying the families," said Dave Hayhoe, the police homicide unit commander.
As searchers combed the river for victims, federal officials looking into the cause of the collapse issued an advisory for states to inspect the metal plates that hold girders together on bridges nationwide.
Investigators said the gussets on the failed Minneapolis bridge were originally attached with rivets, old technology that's more likely to slip than the bolts used in bridges today.
Some of the plates, or gussets, also may have been weakened by welding work over the years and some of them may have been too thin, engineering experts said Thursday.
Questions about the gussets prompted Transportation Secretary Mary Peters to caution states about stress placed on bridges during construction projects.
Investigators are also looking at whether extra weight from construction work could have affected the bridge. An 18-person crew had been working on the Interstate 35W span when it collapsed during the evening rush hour.
Bruce Magladry, director of the National Transportation Safety Board's Office of Highway Safety, said the agency will use a computer to simulate how the bridge might have behaved with different loads, and with different parts of the bridge failing. He said there are infinite combinations to test, so the simulation may have to be run 50 times or 5,000 times.
"Then we compare what the [simulated] collapse looks like to what we actually see out there on the ground," Magladry said, and repeat the simulation until it matches what happened.
NTSB investigators have been trying to pinpoint where on the bridge the collapse began. Observations from a helicopter camera this week found several "tensile fractures" in the superstructure on the north side of the bridge, but nothing that appeared to show where the collapse began, the NTSB said.
Also on Thursday, President Bush dismissed a proposal to raise the federal gasoline tax to repair the nation's bridges at least until Congress changes the way it spends highway money and considers the economic impact of a tax increase.
At the bridge site, recovery crews have removed several vehicles from the river in the last two days. In all, 88 vehicles have been located, both in the river and amid the broken concrete wreckage of the bridge.