A family spokesman says Muhammad Ali died of septic shock "due to unspecified natural causes."
Spokesman Bob Gunnell says Ali died Friday at 9:10 p.m., spending the last hour of his life surrounded by his family. He was initially hospitalized in the Phoenix area on Monday.
His funeral is scheduled for Friday afternoon at the KFC Yum! Center in Louisville, Kentucky.
Eulogies will be given by former President Clinton, Billy Crystal and Bryant Gumbel.
Gunnell says Ali was a citizen of the world and he wanted people of all walks of life to be able to attend. The funeral will be translated and streamed on the Internet.
Also Saturday, one of Ali's daughters is describing her father's last moments, saying his heart wouldn't stop beating for 30 minutes after all of his other organs failed.
Hana Ali writes on Instagram that "no one had even seen anything like it."
She says the family was surrounding Ali, hugging and kissing him, holding his hands and chanting an Islamic prayer while his heart kept beating as his other organs failed.
She calls it a "true testament to the strength of his spirit and will."
