The Mississippi River is closed at Vicksburg for the second time this year.
The Coast Guard says a barge hit a railroad bridge and about 30 of the containers broke free from their tow.
So far half of the containers have been recovered and two sank. Crews are working to wrangle the rest.
No word on when the bridge might reopen.
In January, the river was closed in the same area after tow oil barges hit a rail bridge.
More than 250 gallons of oils spilled into the river.