The drummer's son, Adam Hashian, told sister station KABC, his father was in the middle of a set on stage aboard the Legends of Rock Cruise when he collapsed on Wednesday and died. He was 67 years old.
The Legends of Rock Cruise took off from Miami on March 18 with stops planned in St. Maarten, Puerto Rico and the Bahamas before it was scheduled to return to Miami on March 25, according to the itinerary posted on the cruise's website.
Hashian played on the Boston's first two hit records, their self-titled debut album in 1976, featuring the hit song "More Than a Feeling," and their second album, "Don't Look Back."
The Associated Press contributed to this report.
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