Cruise ship passenger dies at Mystery Island

"Carnival Cruise Line is deeply saddened by the death of a guest on Mystery Island, following what appears to be a medical situation while swimming," a spokeswoman said in a statement.

"Our Care Team is supporting the guest's family along with other guests during this difficult time."

Seven Network reports the passenger was on a nine-day South Pacific voyage aboard the Carnival Splendour.

The ship sailed from Sydney on May 15 and docked at Noumea in New Caledonia on Saturday.

It is expected to return to Sydney on Wednesday.