Authorities were investigating the disappearance of an Ohio woman who was reported missing Monday from a Carnival Cruise Lines ship.

The 37-year-old woman, whose name was not released, had been on a four-day cruise to Key West and Mexico.

The Miami-based cruise line said relatives last saw the woman Saturday night, but did not report her missing until Monday, when the ship returned to Miami. FBI spokeswoman Judy Orihuela said, however, that she was not aware of any delay in reporting the disappearance.

"It doesn't look like foul play," said Orihuela, whose agency is investigating the case.

The disappearance from the Carnival cruise ship Imagination was the latest missing person case involving a cruise this year.

Elizabeth Galeana, 22, of Naples, Fla., apparently fell off a cruise ship in July and drowned. Her body was found off the coast of Italy last month. In May, Daniel DiPiero, 21, of Canfield, Ohio, fell off a cruise ship to the Bahamas after a night of heavy drinking with friends.

One of the highest profile cases involving a cruise ship disappearance occurred last summer, when George Allen Smith IV, 26, of Greenwich, Conn., vanished from his honeymoon cruise in the Mediterranean after an apparent late night of drinking. Bloodstains were found on a canopy that covers lifeboats. No one has been charged and no body has been found.