The US Coast Guard has suspended a search for a 72-year-old American man feared to have gone overboard while on a five-day cruise to Mexico.
The Ruby Princess returned to San Francisco on Monday but there was no sign of the missing traveller when officials scoured the ship and reviewed security video.
Aerial searches of the Pacific Ocean were launched on Monday about 70km off the coast of Monterey, California.
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However, those efforts have now been suspended “pending any new developments,” a Coast Guard spokesperson told the Associated Press.
US Customs and Border Protection are investigating the disappearance.
The Ruby Princess is 290m long and has a capacity of 3000 passengers.
Princess Cruises, which operates the luxury vessel, said it had turned the ship inside out trying to find the man.
“CCTV footage has also been extensively reviewed and the ship was searched thoroughly several times without success,” a spokesperson said.
“Having ruled out other possibilities, this is being treated as a man overboard incident.
“We extend our heartfelt condolences to the family and friends of the guest who was travelling alone.”
The missing traveller is not the first to go overboard on a cruise in recent times, with about 20 similar incidents recorded every year.
The Ruby Princess has since departed San Francisco and is now on a 16-day round-trip of the Hawaiian Islands.