The BAA, which said Thomas died on Tuesday, did not disclose the cause of death.
Thomas first broke the world high jump record in 1960 by clearing 2.17 metres and improved on the record three more times within the next two months before Brumel took over the record with a leap of 2.23 in 1961.
Competing all over the world, the rivalry between Brumel and Thomas, at the peak of the Cold War, was considered one of the most dramatic rivalries in track and field.
Thomas, who as a Boston University freshman became the first athlete to clear seven feet (2.13 m) indoors, cleared that mark or higher 191 times, losing only eight competitions, according to the USA Track and Field Hall of Fame, who enshrined him in 1985.
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