Muhammad Ali, who proclaimed himself "The Greatest" and was among the most famous and beloved athletes on the planet, died at the age of 74 Friday.

By staff & agencies

The legendary boxer passed away in Phoenix after a 32-year battle with Parkinson's disease.

Along with a fearsome reputation as a fighter, he spoke out against racism, war and religious intolerance, while projecting an unshakeable confidence and humor that became a model for African-Americans at the height of the civil rights era.

The three-time World Heavyweight Champion boxer died this evening," Gunnell said in a statement. "The Ali family would like to thank everyone for their thoughts, prayers, and support and asks for privacy at this time."

Ali's daughter Hana Ali said her father was the a "humble mountain."

 "And now he has gone home to God. God bless you daddy. YOU ARE THE LOVE OF MY LIFE!" she tweeted.

George Foreman, who Ali defeated in 1974 for the world heavyweight title, wrote on Twitter, "It's been said it was rope a dope Ali beat me with. (N)o (it was) his beauty that beat me. Most beauty I've know(n). loved him."

Ali went on to win the heavyweight title twice more before retiring for good in 1981.

Ali also was hospitalized in January 2015 with a urinary tract infection. He was hospitalized in December 2014 with pneumonia.

Funeral services will be held in Louisville.