MINNEAPOLIS, Aug. 6 (UPI) -- The remnants of a Minneapolis highway bridge that collapsed last week are unstable and endangering investigators working in the Mississippi River.
National Transportation Safety Board Chairman Mark Rosenker told reporters Sunday parts of the Interstate 35W bridge are breaking away and falling as investigators try to determine what caused the collapse last Wednesday, USA Today reported on Monday.
"It continues to get weaker and weaker the longer it sits there because the integrity of the bridge is gone," Rosenker said.
The afternoon rush-hour collapse killed at least five people, and eight remain missing. About 100 others were injured when the 40-year-old bridge buckled.
Meanwhile, the FBI was adding its underwater evidence recovery team was enlisted to join the search of the river for the missing and evidence as to what caused the structural failure, the report said.
A construction company was doing maintenance on the bridge when it crumbled.