Miss. River Closed During Search for Sunken Tug The Coast Guard has shut down Mississippi River traffic in southeastern Louisiana as the search continues for a sunken tugboat. The 48-foot tug C-Pec sank Saturday afternoon. The cause isn't known. The Coast Guard says two people aboard were rescued. Near Venice, river traffic was shut down in both directions from around the mouth of the river up to mile marker 10. The Coast Guard says it will reopen after the submerged vessel is located and authorities are sure the river can be safely navigated. Petty Officer Carlos Vega said about 24 vessels awaited passage as of Sunday morning. Carnival Cruise Lines says its ship the Conquest was diverted from New Orleans to Mobile, Ala. It's expected to arrive Sunday afternoon, and passengers will be driven to New Orleans.