Mike Tyson, Lennox Lewis, Will Smith to serve as pallbearers for Muhammad Ali's funeral

Heavyweight boxing greats Mike Tyson and Lennox Lewis, actor Will Smith, and members of Muhammad Ali's family will serve as pallbearers for the late three-time heavyweight champion's funeral on Friday in Louisville, Kentucky, a 19-mile procession that will "tour landmarks of Ali's life" in the city where he was born and raised.

Tyson took a red-eye flight from Las Vegas to Louisville to be there for the service, after initially being unsure if he would be able to attend, or if he would be able to handle the emotions of the event. Tyson was reportedly "highly emotional" when he heard of Ali's death last week.

Ali died at the age of 74 on Friday, June 3, in a hospital in Phoenix, Arizona. He had been admitted to the hospital on Thursday, June 2, with a respiratory condition, which quickly took a turn for the worse.

A public memorial service will be held at 2 p.m. ET today at the KFC Yum! Center in Louisville. Among the speakers will be former President Bill Clinton, actor Billy Crystal, journalist Bryant Gumbel, Ali's daughter Maryum Ali, and representatives from multiple faiths.