MINNEAPOLIS, Aug. 2 (UPI) -- Crews were checking boxcars crushed by the Interstate 35W bridge collapse to rule out a hazardous material threat, a Minneapolis official said Thursday.
Pollution containment crews were assessing train cars compressed when the bridge suddenly fell into the Mississippi River and its banks during evening rush hour Wednesday.
At least four people were confirmed dead, scores sent to area hospitals and 20 were reported missing.
One car contained a substance "preliminarily identified" as polystyrene bead, Minneapolis Fire Chief Jim Clack said during a briefing. The beads are not considered hazardous.
"There is not an immediate hazardous threat, but we will continue to monitor" and check rail car wreckage, Clack said. The number of cars affected was not immediately known.
Recovery operations in the Mississippi River resumed Thursday.
The Interstate 35W Bridge near the University of Minnesota and downtown Minneapolis normally runs eight lanes of traffic; however construction reduced the number of lanes opened to two. More than 100,000 cars per day travel over the bridge, according to the Minnesota Department of Transportation.
