What started out as a vacation with friends now has become the latest cruise ship mystery.
Royal Caribbean's Mariner of the Seas was sailing from Port Canaveral, Fla., to its first port of call in the Bahamas. But Daniel DiPiero, 21, of Canfield, Ohio, never made it.
DiPiero was traveling with six friends, who say he left them around midnight on Sunday to return to their shared stateroom. Later, between 12:12 a.m. and 2:16 a.m., ship security cameras captured him standing along a railing and reclining in a chair on a side deck. With no evidence that he had ever slept in their cabin, the friends reported DiPiero missing at 11 a.m. on Monday.
So far, searches on the ship and by air have turned up no clues. Severe weather, however, has hindered the search. The Coast Guard in Miami has dispatched a cutter, and today a Coast Guard aircraft will be searching the Bahamas waters.
"We have had a number of cases where we've been fortunate enough to locate the person. We've had assets that were on scene very quickly after the person had gone over and been able to recover them," Coast Guard Lt. Cmdr. Jeff Smith said today.
DiPiero is the 12th person to go missing from a cruise ship in the last two years. In July, another Royal Caribbean passenger, George Smith, 26, disappeared while on his honeymoon in the Mediterranean. Fellow passengers heard a loud noise from his cabin, and in the morning there was blood below his balcony. Smith has never been found.
Having received criticism for its handling of that incident, Royal Caribbean released a statement Tuesday about its investigation into DiPiero's disappearance.
"The company is fully supporting the search and investigation in numerous ways, including the collection of onboard records, videos and statements, and preserving the area on deck four and the young man's stateroom for investigators," the statement said.
DiPiero's family has already reached out to Kendall Carver, president of International Cruise Victims, an organization that provides assistance to families of missing loved ones.
"It's a feeling of desperation, and unfortunately it doesn't fade away," Carver said. "As the weeks progress, the feeling of pain only increases."
ABC News' Jeffrey Kofman originally reported this story for "Good Morning America."