Former world heavyweight boxing champion Muhammad Ali hits a heavy bag during a visit to the Sahat Homa Boxing Club to watch local boxers train November18, 2002 in Kabul, Afghanistan

Muhammad Ali’s cause of death was septic shock, a family spokesperson told reporters in Phoenix on Saturday, one day after the boxing legend passed away at age 74.

Ali died at 9:10 p.m. local time in an Arizona medical facility, surrounded by his family. The official cause of death was “septic shock due to unspecified natural causes,” said spokesman Bob Gunnell.

Gunnell revealed that Ali was hospitalized last Monday and not Thursday, as was widely reported.

Also Read: Muhammad Ali Mourned by Hollywood, Sports Royalty

Ali’s body is expected to be transported to his hometown of Louisville, Kentucky, where he will be laid to rest on Friday in a public funeral service.

Gunnell said the services will begin with a procession through the streets of the city. The funeral will take place at the KFC YUM! Center and be led by an imam in the Muslim tradition.

Bill Clinton, Billy Crystal, and Bryant Gumbel will be among the eulogizers. A private, family-only burial will follow.

The boxer was admitted to an Arizona hospital for respiratory issues but as the days went by his condition deteriorated. Hana Ali, one of Muhammad’s daughters, recounted her father’s final moments on Twitter:

“All of use were around him hugging and kissing him and holding his hands, chanting the Islamic prayer. All of his organs failed but his HEART wouldn’t stop beating. For 30 minutes … his heart kept beating. No one had ever seen anything like that. A true testament to the strength of his SPIRIT and WILL!”

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Other tributes continue to pour in for the former world and Olympic champion.

President Obama tweeted, “He shook up the world, and the world’s better for it. Rest in peace, Champ.”

George Foreman, Ali’s opponent-turned-lifelong friend, described him as “a fine man” and “royalty.”

Muhammad Ali's 75th Birthday: 13 Jaw-Dropping Moments From His Boxing Career (Photos)

Muhammad Ali was born Cassius Marcellus Clay Jr. in 1942 in Louisville, Kentucky. As a young boy, Clay was first introduced to the world of boxing when his red-and-white Schwinn bicycle was stolen. An upset Clay reported the incident to a police officer Joe Martin, who happened to be a boxing trainer, and suggested the boy learned how to fight. Martin went on to become Clay's trainer throughout his six-year amateur career.
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Clay won the gold medal at the 1960 Summer Olympics in Rome for light heavyweight boxing, despite almost not competing on the U.S. team due to his fear of flying.
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Clay made his debut as a professional boxer on Oct. 29, 1960 and earned the nickname "Louisville Lip" for both his verbal taunts and distinctive style.
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Clay became the heavyweight champion of the world on Feb. 25, 1964, after defeating reigning champion Sonny Liston. It was at this match that Clay coined the iconic phrase “float like a butterfly, sting like a bee.”
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The day after the match, Clay confirmed in a press conference that he had converted after joining the Nation of Islam. He renounced his last name and called himself Cassius X until March 6, 1964, when Elijah Muhammad of the Nation of Islam gave him his official holy name, Muhammad Ali.
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Ali refused to fight in the Vietnam War for religious reasons -- a decision that led to the New York State Athletic Commission suspending his boxing license and revoking his heavyweight belt. He was also arrested for draft evasion, but the Supreme Court eventually overturned his conviction on June 28, 1971.

Also Read: Muhammad Ali’s Ex Reveals What It Was Like to Be Married to the Champ
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Coined as the “Fight of the Century,” Ali fought against defending heavyweight champion Joe Frazier -- who had received Ali's title after it was stripped from him -- on March 8, 1971. The fight was Ali’s first defeat as a pro boxer, as he was knocked out after 15 rounds.
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The 32-year-old later defeated 25-year-old champion George Foreman in 1974 in a bout dubbed “The Rumble in the Jungle,” regaining the Heavyweight Champion of the World title that was taken from him.
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Despite losing the heavyweight championship title to Leon Spinks in February 1978, Ali regained the title seven months later, making him the first boxer to win the heavyweight champion title three times.
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The champion boxer officially retired at 39 years old after losing a match to Trevor Berbick in 1981. He was later diagnosed with Parkinson’s in 1984.

Also Read: Boxing Legend Muhammad Ali Recovering After Being Hospitalized With Pneumonia
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Ali was inducted into the International Boxing Hall of Fame in 1990.
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In 2005, President George W. Bush presented Ali with the Presidential Medal of Freedom, the highest civilian award in the nation.
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The boxer and philanthropist opened the $60 million Muhammad Ali Center in Louisville, Kentucky, in 2005. The cultural center, which focuses on social responsibility, also serves as a museum dedicated to Ali's career.
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A look back at the athlete known as simply “The Greatest,” who would have turned 75 on Tuesday

Muhammad Ali was born Cassius Marcellus Clay Jr. in 1942 in Louisville, Kentucky. As a young boy, Clay was first introduced to the world of boxing when his red-and-white Schwinn bicycle was stolen. An upset Clay reported the incident to a police officer Joe Martin, who happened to be a boxing trainer, and suggested the boy learned how to fight. Martin went on to become Clay's trainer throughout his six-year amateur career.

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