Muhammad Ali's body has arrived in his hometown of Louisville, Kentucky, where he will be laid to rest on Friday.

The boxing legend's coffin was flown to an airport in the city before being carried into a hearse and driven away.

His family have said a public memorial will be held at a sports arena in the city later this week, with thousands of mourners expected to attend.

Former US president Bill Clinton and comedian Billy Crystal are among those delivering eulogies at the ceremony, which will be led by an imam in line with Muslim tradition.

Representatives of other faiths will also attend, and family spokesman Bob Gunnell said: "The celebration will reflect his devotion to people of all races, religions and backgrounds."

A private service will be held a day before the public memorial, which will be streamed online.

Flowers, cards and signs have been placed outside his childhood home in the city, and flags have been flying at half-mast.

Tributes have been paid to Ali from countless figures in sport, showbiz and politics, with US President Barack Obama saying the boxing icon "fought for what was right" both inside and outside the ring.

According to Mr Gunnell, Ali's official cause of death was septic shock "due to unspecified natural causes".

Earlier in the week he was admitted to hospital with respiratory issues linked to Parkinson's disease, which he had been diagnosed with in 1984.

Mr Gunnell said Ali's wife and nine children had been hopeful that his stay in hospital would be brief, but were called to his bedside when his condition became more serious.

"They had a full day to say farewell to Muhammad. All family members, all daughters and his son were in attendance, and his wife," the family spokesman told reporters.