Ward, 41, was found unconscious in a hot tub on the Carnival Dream last Friday, the Philadelphia Daily News reported. After the ship docked Saturday in Port Canaveral, Fla., his body was taken to the medical examiner's office in Brevard County, but a spokesman says the cause of death has not been determined because toxicology tests will take several weeks.
Andino Ward, Michael's father, said he and his son were on vacation with other relatives.
MOVE, founded in Philadelphia in 1972, combined African nationalism with a back-to-nature philosophy. Its members all took the surname Africa.
Ward, whose parents had separated, became involved with the group through his mother. The two were living in the group's house in West Philadelphia when police attempted to arrest MOVE members in May 1985.
Police used explosives targeted at a bunker on the roof, setting off a fire that destroyed the MOVE house and spread to the rest of the block. Six adults, including MOVE founder John Africa and Ward's mother, Rhonda Africa, died in the fire, along with five children. Only two people got out, Ward and an adult, Ramona Africa.
While Ward rarely spoke publicly about his time in MOVE, he did describe being brought up without learning how to read and write and not having enough to eat.
Ward spent his teenage years with his father in Lansdale, Pa., a Philadelphia suburb. He served in the Army, married and had two children, although the marriage ended in divorce, and worked as a truck driver.
Philadelphia agreed to pay Ward and his father almost $900,000 in a single payment in 1991 with a stipend of $1,000 a month after that.