Mike McCallum, one of boxing’s most accomplished and respected champions of the 1980s and 1990s, died suddenly Saturday in Las Vegas.

McCallum, who won world titles in three weight classes and became a successful trainer once he retired, was 68.

According to reports out of his native Jamaica, McCallum felt ill while he was driving to a gym in Las Vegas where he trained fighters. The Jamaica Observer reported that McCallum was found unresponsive and later pronounced dead.

Olivia Grange, Jamaica’s sports minister, confirmed McCallum’s death in a statement.

“It is with utter and complete sadness that I learned of the death of Jamaica’s three-time world boxing champion Michael McKenzie McCallum,” Grange said. “I express my personal condolences to his mother, siblings and his children. On behalf of the Ministry of Sports, I take this opportunity to extend our sympathies to the family and friends of this legendary Jamaican.”

McCallum was born in Kingston, the Jamaican capital, on Dec. 7, 1956. He represented Jamaica at the 1976 Summer Olympics in Montreal and remained an amateur for four more years before he made his pro debut in January 1981.

A proficient technician with power, a high ring IQ and a granite chin, McCallum became known as “The Body Snatcher” because he often hurt and knocked out opponents with body punches. His left hook to the body instilled fear in many of his opponents and he was never knocked out in 55 professional fights.

He was a champion in the junior middleweight, middleweight and light heavyweight divisions. McCallum competed professionally for 16 years, retired with a record of 49-5-1, including 36 knockouts, and was inducted into the International Boxing Hall of Fame in 2003.

The Ring named him its eighth best middleweight champion in boxing history in 2011. Though a first-ballot Hall of Fame fighter, McCallum admitted he was frustrated at times because the highest-profile fighters of his era — namely “Sugar” Ray Leonard, Thomas Hearns, Marvin Hagler and Roberto Duran — wouldn’t fight an opponent considered to be a high-risk, low-reward assignment.

McCallum won his first world title in October 1984, when he defeated Sean Mannion by unanimous decision in a 15-round fight for the vacant WBA 154-pound crown at Madison Square Garden in New York. That win made McCallum boxing’s first Jamaican-born world champion.

McCallum made six successful defenses of that WBA belt and won all six of those bouts by knockout. Three of those stoppages were recorded against top 154-pound opponents — Julian Jackson, Milton McCrory and Donald Curry — from August 1986-July 1987.

Fourteen months after Sumbu Kalambay upset McCallum to retain his WBA middleweight title, he traveled to London and defeated England’s Herol Graham by split decision to win the WBA middleweight title in May 1989. McCallum defended that belt three times, including a split-decision victory over Kalambay in their rematch in April 1991.

At the advanced age of 37, McCallum became a three-division champion in March 1994. He stopped Randall Yonker in the fifth round of that bout to win the vacant WBC light heavyweight title.

McCallum retired after rival James Toney beat him by unanimous decision in their third fight, which took place in February 1997. Toney previously defeated McCallum by majority decision in August 1992 and fought him to a draw in December 1991.

Three of McCallum’s five losses came against Toney and Roy Jones Jr., two fellow Hall of Fame fighters. Toney often calls McCallum the best opponent he fought during his celebrated career.

In retirement, McCallum was praised for his work as a trainer in gyms throughout Las Vegas. He often worked alongside his friend, fellow former champion Eddie Mustafa Muhammad.