A barge has sunk near the LaSalle Street bridge on the Chicago River.

The barge, which belongs to a construction company doing work along the riverwalk, started taking on water early this morning, according to Pete Scales, a spokesman for the Chicago Department of Transportation.

The barge, which is about 50 feet by 20 feet, is now completely submerged, Scales said. No one was on board when it sank.

The barge is within a construction zone on the river's edge, and river traffic can still get by, Scales said.

A marine salvage company is on its way to bring the barge to the surface. The process, which will involve pushing air back into parts of the barge that took on water, could take days, Scales said.

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