"It is with great sadness that we can confirm our beloved son, brother and friend George passed away peacefully at home over the Christmas period," Efe news agency cited a statement by his publicist.
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"The family would ask that their privacy be respected at this difficult and emotional time. There will be no further comment at this stage," the statement continued.
Michael -- who was born in London and whose real name was Georgios Kyriacos Panayiotou -- sold more than 100 million albums during his musical career lasting almost four decades. He was well-known for his 1984 solo single "Careless Whisper".
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An ambulance reportedly was called to Michael's home at about 1.42 p.m. (local time) on Sunday afternoon, and local police said there there appeared to be no suspicious circumstances surrounding his death.
In 2011, Michael was forced to cancel several concerts after being hospitalised for a very serious case of pneumonia.
Michael had skyrocketed to fame with his childhood friend Andrew Ridgeley as members of the pop duo "Wham!" in the early 1980s.
After leaving that group, Michael launched a solo career that included huge hits such as "Listen Without Prejudice Vol. 1".
Earlier, he had released "Faith". an album that Michael arranged, produced and wrote practically alone that went platinum four times over in the United Kingdom.
IANS