Tributes have poured in for Muhammad Ali, the heavyweight champion boxer who transfixed the world with his sporting feats, quick-witted commentary and civil rights activism. 

Muhammad Ali, 1942-2016

Muhammad Ali was born Cassius Marcellus Clay Jr on January 17, 1942, in Louisville, Kentucky

Aged 22, he took on heavyweight champion Sonny Liston in Miami. He won and proclaimed to the world: "I am the greatest!"

Ali was the first man to win heavyweight titles three times

Ali attended his first Nation of Islam meeting in 1959 and converted to Sunni Islam in 1975

In 1967, he famously refused to fight in Vietnam, citing religious reasons

Married four times, he had seven daughters and two sons

He was diagnosed with Parkinson's disease in 1984, at the age of 43

Ali died late on June 3, 2016, in a hospital in Arizona after being admitted with respiratory problems

Ali's funeral will take place in Louisville

Ali is survived by his wife, the former Lonnie Williams, who knew him when she was a child, along with his nine children

Ali, who died aged 74 late on Friday, had endured a long fight with Parkinson's disease.

US President Barack Obama, who keeps a pair of boxing gloves worn by Ali in his private study, said on Saturday that Ali "shook up the world and the world is better for it".

He added Parkinson's disease may have "ravaged" Ali's body, but it "couldn't take the spark from his eyes".

Fellow athletes were quick to offer their condolences.

"A part of me slipped away," George Foreman said on Twitter, calling the legendary fellow boxer by his "the Greatest" nickname.

"God came for his champion. So long great one," boxer Mike Tyson said on Twitter.

"RIP to The Greatest Muhammad Ali, you have given something to boxing that will never be forgotten," tweeted Floyd Mayweather.

British boxer Amir Khan, meanwhile, offered "prayers and thoughts".

Manny Pacquiao, the Filipino former world champion professional boxer, said the boxing world would benefit from Ali's legacy.

"We lost a giant today," said Pacquiai. "Boxing benefited from Muhammad Ali's talents but not nearly as much as mankind benefited from his humanity."

Artists, activists and politicians also paid tribute to the late boxer.

Michael Moore, the documentary filmmaker, said: "Muhammad Ali, pacifist, Muslim. Convicted as a felon simply because he refused to go to Vietnam." He quoted Ali's famous line: "No Vietnamese ever called me a n*****."

Source: Al Jazeera