The U.S. Coast Guard is scouring the waters northwest of Puerto Rico for a 20-year-old Royal Caribbean crew member who went overboard the cruise ship. Teams are looking for Arron Hough, from the United Kingdom, a member of the Harmony of the Seas’ entertainment team who reportedly failed to show up for work on Christmas Day. The ship’s closed-circuit camera footage showed him walking into an area on Deck 5 at around 4 a.m. but he was not seen again, according to a statement from Royal Caribbean. Officials aboard Harmony of the Seas— the world’s largest cruise ship—alerted Coast Guard Sector San Juan on Christmas Day about the missing crew member. Hough is reportedly the fifth person to go overboard a cruise ship since November. A 22-year-old autistic man from Georgia went overboard on a Mexico-bound Carnival Fantasy cruise this month, according to CNN.