Rescuers are searching for the missing crew members of a large commercial vessel after it capsized off the US state of Louisiana.

The US Coast Guard confirmed one person was found dead and six others have been rescued.

Twelve people are missing.

A spokesman said the search team was “giving it all we got” and remained optimistic.

The lift boat capsized about eight miles (12km) from Port Fourchon on Tuesday afternoon.

The 129ft (39m) vessel was identified as belonging to marine transport firm Seacor Marine.

A lift boat is a self-propelled vessel with an open deck, often using legs and jacks, and is deployed to support drilling or exploration.