The FBI is probing the recent death of a passenger on a Royal Caribbean cruise ship while he was detained for alleged belligerence toward others on board.

“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 agency told ABC News.

Another passenger who was on board claims the deceased, Michael Virgil, 35, threatened him and his family and was violent with crew members less than an hour after the boat left the Los Angeles port of San Pedro.

“The gentleman that was drunk said he was going to kill us. He started chasing us down the hallway,” passenger Christifer Mikhail told Los Angeles Fox affiliate KTTV.

Mr. Mikhail also accused Mr. Virgil of kicking one crew member in the face while wearing a steel-toed boot and punching another crew member. Cellphone footage purportedly shows Mr. Virgil trying to kick down a door to get at a crew member hiding inside.

Mr. Virgil was eventually stopped and restrained with bear or pepper spray, zip ties and handcuffs.

Mr. Virgil’s family said his alleged behavior was uncharacteristic and accused Royal Caribbean staff of injecting him with an unspecified sedative that led to his death.

“He didn’t deserve to die over it,” an unnamed relative of Mr. Virgil told KTTV.

The Los Angeles County Medical Examiner lists Friday as when Mr. Virgil died. His cause of death is pending further investigation.

“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,” Royal Caribbean told ABC News.

• Brad Matthews can be reached at bmatthews@washingtontimes.com.