The US Coast Guard (USCG) closed a stretch of the Mississippi River on Thursday after a general cargoship spilled oil following a collision.
The USCG said the leak came from the 27,700-dwt Pac Antares (built 2003), which is listed by Equasis as operated by Pacific Carriers' PACC Ship Managers.
A 10-mile section was shut in New Orleans.
This halted 12 vessels, USCG chief petty officer third class Travis Magee told Reuters.
It was unclear when it would be reopened.
The ship was carrying silicon manganese when it hit a pier, causing diesel to spill, according to the USCG.
PACC Ship Managers confirmed the incident.
"The vessel, while maneuvering to berth with a pilot on board, came in contact with an object which caused a bunker spill," it said.
"The crew immediately notified all appropriate authorities and are working with professional response contractors, the US Coast Guard and local authorities to mitigate the situation.
"The source of the spill has been contained and there are no injuries to the crew."
Authorities had earlier warned of strong currents due to a thaw.
AIS data shows the vessel moored near New Orleans on Friday.
