Pop superstar George Michael's death from suspected heart failure has prompted an outpouring of shock and sadness from celebrity friends and fans.
The 53-year-old's death is being treated by police as "unexplained but not suspicious" after his body was discovered on Christmas Day.
Michael, who rose to fame as the front man of Wham! and had chart-topping hits including Last Christmas and Freedom, died peacefully at home, his publicist said.
The cause of the star's death was heart failure, according to his manager Michael Lippman.
Michael - whose real name was Georgios Kyriacos Panayiotou - sold more than 100 million albums throughout a career spanning almost four decades.
Big names from the world of entertainment paid tribute after hearing about his death, which comes in a year that has seen the music industry lose some of its biggest stars including Prince, David Bowie and Leonard Cohen.
Sir Elton John posted a photograph of himself and Michael on Instagram, writing: "I am in deep shock. I have lost a beloved friend - the kindest, most generous soul and a brilliant artist. My heart goes out to his family and all of his fans."
Michael's former Wham! bandmate Andrew Ridgeley said he was "heartbroken at the loss of my beloved friend Yog", an affectionate nickname used for the star.
He said: "Me, his loved ones, his friends, the world of music, the world at large. 4ever loved. A xx"
Friend Madonna paid her own tribute, posting an undated video on Twitter in which she embraced Michael on stage. In it she tells the audience: "He's a great songwriter and he makes very classy videos, like me."
Referencing several of his best known lyrics, she adds: "George, I want your sex, so be my father figure and I will have faith if we have to live hand-to-mouth. The diva himself."
Michael formed Wham! with Ridgeley in 1981, and went on to massive success, releasing a string of hit singles including Wham Rap! (Enjoy What You Do), Club Tropicana, Wake Me Up Before You Go Go, and Last Christmas.
They were the first Western pop act to visit China when they played there in 1985, before splitting in 1986, by which time Michael had already released a handful of solo singles.
Fans and neighbours gathered at his homes in Highgate, north London and Goring-on-Thames in Oxfordshire to pay tribute to an artist they described as a "huge inspiration".
People visited to lay flowers, light candles and recalled memories of listening to his music, seeing him live or meeting him.
On Sunday night, Thames Valley Police said they were called to a property in Goring-on-Thames shortly before 2pm, adding: "Sadly, a 53-year-old man was confirmed deceased at the scene.
"At this stage the death is being treated as unexplained but not suspicious. A post-mortem will be undertaken in due course."
A woman on 'Deal Or No Deal' told us she needed £15k for IVF treatment. George Michael secretly phoned the next day and gave her the £15k.— Richard Osman (@richardosman) December 26, 2016
The star's publicist said: "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.
"The family would ask that their privacy be respected at this difficult and emotional time. There will be no further comment at this stage."
As well as being known for his talents, Michael had a turbulent personal life, as brushes with the law and tales of drug use saw him hit the headlines.
I've loved George Michael for as long as I can remember. He was an absolute inspiration. Always ahead of his time.— James Corden (@JKCorden) December 25, 2016
He nearly died from pneumonia in late 2011, and after receiving treatment in a Vienna hospital, he made a tearful appearance outside his London home and said it had been ''touch and go'' whether he lived.
Doctors had performed a tracheotomy to keep his airways open and he was unconscious for some of his spell in hospital.
Meanwhile, Michael's 1990 album Listen Without Prejudice Vol. 1 had been set to be reissued accompanied by a new film featuring Stevie Wonder, Sir Elton and the supermodels who starred in the video to his hit single Freedom! '90.
George Michael was a kind and gentle soul. #Wham— Ryan Reynolds (@VancityReynolds) December 26, 2016
An appeal for archive footage and imagery from fans including "mass Wham! hysteria" had been made on Michael's website in August, with a post on his official Facebook page saying: "George is personally seeking rare Wham! & George Michael photos and video and we need your help!"
The movie, with the working title Freedom: George Michael, was to be narrated by Michael and set to feature Mark Ronson, Mary J Blige, Tony Bennett, Liam Gallagher, James Corden and Ricky Gervais.
The record was his second solo album, after the hugely successful Faith, and was arranged, produced and written almost entirely by Michael, but did not feature him on the album cover.
It featured hits including Cowboys And Angels, Mother's Pride and Praying For Time and outsold Faith in the UK, where it went platinum four times but led to a court case with US record label Sony about Michael's frustration over how the album has been marketed. Michael lost the case.
Spandau Ballet star Martin Kemp and his wife Shirlie - a backing singer for Wham! with her musical partner Helen "Pepsi" DeMacque as part of the act Pepsi & Shirlie - have both paid tribute to Michael.
Kemp wrote on Twitter: "My whole family and I are devastated at the loss of our beautiful friend Yog! We will miss him so much! We are all heartbroken!"
Shirlie wrote that she is "beyond heartbroken".
She added: "Words cannot express how sad we all are, only last week I saw him laughing and happy. My heart is broken to lose someone so special."
Kemp previously revealed how Michael was responsible for his getting with Shirlie, to whom he has been married since 1988.
George Michael RIP. Your music lifted our spirits. Your heart was pure. Sad. You will be missed.— Goldie Hawn (@goldiehawn) December 26, 2016
Michael introduced Shirlie to Kemp in the 1980s and joined them on their very first date.
Speaking to Piers Morgan on his Life Stories programme in 2014, Kemp said: "'He's a special person, George. He's been a good friend to us for years.
In Memoriam of George Michael, 1963-2016 pic.twitter.com/b70ImfblTh— billboard (@billboard) December 26, 2016
"It's funny because I remember the first date that Shirlie and I ever went on. George came as a chaperone. I spent the whole evening trying to lose him so that me and Shirlie could sneak off somewhere and snog.
"He's a special person and he always will be."
Currently six of Michael's albums and four singles feature in the top 100 iTunes chart.
His album Ladies and Gentlemen is at number three, while one of his best-known tracks Careless Whisper is at number 32 in the singles chart.