The United States Coast Guard is searching for an 18 year-old who fell overboard a boat while fishing about 180 kilometres south of American Samoa.
The seaman fell out of the vessel, the Siva Moana, trying to recover fishing gear.
A Royal New Zealand Air Force P-3 Orion and a US Coast Guard Hercules aircraft have been searching for the sailor.
The head of the local Coast Guard Detachment Unit, Lieutenant Steven Caskey, says the unit is not involved in the search but will conduct an investigation once the Siva Moana arrives in port.
The Siva Moana remains in the area and is assisting in the search.