The FBI is investigating an incident aboard a Royal Caribbean cruise ship allegedly involving an unruly passenger.

       The incident took place Friday aboard the Navigator of the Seas, which was sailing from Ensenada, Baja California, to Los Angeles, officials said.

       The unidentified passenger allegedly became unruly and crew members were called in, according to witnesses.

       A video of the incident showed crew members restraining the man on the floor with towels.

       It is unclear when the man died after being restrained.

       "The FBI responded to a Royal Caribbean cruise on Monday when it docked in Los Angeles and is investigating an incident on board that resulted in death," the FBI said in a statement.

       Royal Caribbean Cruises released a statement after the incident, saying, "We are saddened by the passing of one of our guests. We offered support to the family and are working with authorities on their investigation."