Boxing legend Muhammad Ali has been laid to rest in his hometown in the US state of Kentucky, following a funeral procession attended by tens of thousands of fans.  

Ali's private burial ceremony on Friday at Louisville's Cave Hill Cemetery, was followed by a memorial, attended by world leaders including former US president Bill Clinton.

As the interfaith service got under way, the crowd of up to 15,000 burst into applause and chanted, "Ali! Ali!"

Ali died last week at the age of 74.

Speaking at the service the former US president said Ali was a man who "decided very young to write his own life story":  

Muhammad Ali's widow paid tribute to her husband. Lonnie Ali took to the stage of a packed sports stadium. She thanked the world for "heartfelt expressions of love" since the boxing legend's death last week.

Billy Crystal also paid his respects to the 74 year-old, likening Ali's uniqueness to that of Mozart and Picasso.

The actor and comedian said Ali became a "silent messenger of peace who taught us that life is best when you build bridges between people, not walls".

During his speech he also did an impression of 'The Greatest', and received big laughs from the guests.