Mike McCallum, the legendary Jamaican boxer known as “The Bodysnatcher,” has died. He was 68.

The athlete was driving to the gym in Las Vegas on Saturday, May 31, when he fell ill and pulled off the road, according to The Jamaica Observer.

McCallum was later found unresponsive and then declared dead, the outlet reported. His official cause of death has not yet been revealed.

PEOPLE reached out to the Las Vegas Metropolitan Police Department (LVMPD) for comment on Sunday, June 1, but did not receive an immediate response. 

McCallum — who was nicknamed “The Bodysnatcher” for his hard-hitting punches — was the first Jamaican to win the world title in 1984 when he defeated Sean Mannion of Ireland at Madison Square Garden in New York City.

He was also a hall-of-fame fighter who held world titles in three different weight classes, and his career included a total of 55 fights, of which he won 49, lost five and tied one, per Boxing Undedfeated.

Out of his 49 wins, 36 were “knockouts” — which left his opponents unable to stand back up after a referee’s count to 10.

McCallum was inducted into the International Boxing Hall of Fame in 2003.

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Olivia Grange, Jamaica’s Minister of Sport, posted a tribute to McCallum on Instagram after his death.

“I take this opportunity to extend our sympathies to the family and friends of this legendary Jamaican,” she wrote.