PITTSBURGH, Pennsylvania: This week, a stretch of the Ohio River near Pittsburgh remained closed to maritime traffic as crews equipped with sonar searched for a barge that is believed to have sunk over last weekend.

The barge is one of more than two dozen that broke loose and floated down the river after heavy rains.

After 26 river barges, with all but three of them loaded with coal, fertilizer and other dry cargo, detached from their moorings late on April 12, striking a bridge and smashing a pair of marinas, the U.S. Coast Guard launched a subsequent investigation.

Pittsburgh police and Coast Guard officials said no injuries were reported and no hazardous materials spilled into the river. Still, the river will be off limits to mariners so the barges’ owner can salvage the missing vessel.

As the area had been hit by flooding after heavy rains on Thursday, Coast Guard investigators looked at high water as a possible cause or factor, said Commander Justin Jolley of the Coast Guard Marine Safety Unit in Pittsburgh.

Alan Nogy, operations project manager of locks and dams at the U.S. Army Corps of Engineers Pittsburgh District, said that high water could pose a risk for tied barges, which occasionally break loose on the Ohio River.

Seven barges were still stuck at the Emsworth Locks and Dam, while another was pinned against the Dashields Locks and Dam several miles downstream.

Campbell Transportation Co. owns or operates the barges that wrecked dozens of boat slips at the Branchport Boat Club.

American Waterways Operators, a trade group representing tugboat and barge companies, said it is awaiting the outcome of a probe to “gain further insight as to what occurred.”

It added that barges “safely and efficiently” move 58 million tons of cargo on Pennsylvania waterways every year.