Mohammed Ali's Family Spokesman Reveals Boxing Legend's Cause of Death

Boxing legend Muhammad Ali died of septic shock after spending five days at an Arizona hospital for what started out as respiratory problems and gradually worsened, succumbing only after his wife and children arrived at his bedside to say goodbye, a family spokesman said Saturday.

"It was a solemn moment," Bob Gunnell told reporters in Phoenix.

The details came as Ali's family revealed plans for a Friday funeral in his hometown of Louisville, Kentucky, a daylong affair that will include a procession through the streets where the 74-year-old world champion grew up and learned to box. His body is expected to be returned to the city within two days.

 The service will include eulogies from former President Bill Clinton, journalist Bryant Gumbel and comedian Billy Crystal. He'll be buried in a local cemetery with only family watching.

In preparation, Louisville lowered flags in mourning on Saturday as it looked toward Ali's final homecoming.

Outside the Muhammad Ali Center, locals created an impromptu memorial, leaving flowers and written tributes.

A few blocks away at Louisville Metro Hall, Mayor Greg Fischer marveled at the many outsize roles Ali embodied: sports champion, civil rights icon, humanitarian and "interfaith pioneer."

"The 'Louisville Lip' spoke to everyone," Fischer said, referring to the dismissive nickname the press gave the boastful Ali early on his career. "But we heard him in a way no one else could, as our brother, our uncle and our inspiration."

Ali, who had suffered for more than three decades from Parkinson's disease, had survived several death scares in recent years, so when he was admitted Monday with breathing problems his family expected him to rebound, Gunnell said.

Then things turned serious, and it became clear that he wasn't going to improve.

His family traveled to his bedside, where they remained for about a day before Ali died at 9:10 p.m. local time on Friday. The official cause of death was "septic shock due to unspecified natural causes," Gunnell said.

Septic shock refers to an aggressive, full-body inflammatory response to an infection, and is common among the elderly and those with weak immune systems. The blood pressure plummets, leading to organ failure.

NBC news cullage.