A woman pays her respects to David Bowie in front of a mural to the late British singer in Brixton, south London, on January 11, 2016
London (AFP) - Music legend David Bowie was famously private during his lifetime but also in his death, with a string of questions about the circumstances of his passing still unanswered Tuesday.
News of his death at the age of 69 was announced in a brief posting early Monday on his official Facebook and Twitter accounts, with a request for privacy for his grieving family.
"David Bowie died peacefully today (Sunday) surrounded by his family after a courageous 18-month battle with cancer," it said.
But little information was available on how or where he died, and requests for comment from Bowie's record company Columbia Records were not answered.
Born and raised in south London, Bowie was a long-time resident of New York and some British media said he had died there.
But the New York Post said the "Heroes" and "Life On Mars?" singer had "passed away at his London home".
With no official comment available, Bowie's place of death remained a mystery, as did funeral arrangements.
Only a small circle of close collaborators were aware that the iconic performer, who repeatedly reinvented himself across six decades in the music industry, was in poor health.
Belgian theatre director Ivo Van Hove, who worked closely with Bowie on his musical "Lazarus" which opened in New York in December, told Dutch public radio NPO that Bowie had been suffering from liver cancer.
"I've known for more than a year," Van Hove told NRC Dutch daily.
"We began working together on our show 'Lazarus', and at one moment he took me to one side to say that because of his illness, he would not always be able to be around."
- Circle of secrecy -
Bowie's success in keeping his illness hidden from the public was praised in an opinion piece in British magazine The Spectator.
"In this era of too much information, when over-sharing is virtually mandatory, Bowie's decision to suffer away from the limelight, among those closest to him, appears almost as a Herculean achievement," wrote commentator Brendan O'Neill.
Bowie's supermodel wife Iman, who has not commented publicly on his death, posted poignant messages on social media before he passed away.
"Sometimes you will never know the true value of a moment until it becomes a memory," she wrote on her public Twitter and Facebook accounts on Saturday.
Bowie's son, film director Duncan Jones, commented only to confirm the news with a short Twitter message: "Very sorry and sad to say it's true. I'll be offline for a while. Love to all."
All but an inner circle were kept in the dark about the singer's illness as he worked to complete his final album, "Blackstar", released on his 69th birthday, just two days before his death.
Van Hove said Bowie was desperate to finish "Blackstar" and "Lazarus" before it was too late.
At the musical's New York premiere on December 7, few knew that anything was amiss.
"The press wrote that he looked so well and so healthy. But as we went off the stage, he collapsed. And I realised that it might be the last time I saw him," said Van Hove.
Tony Visconti, who worked with Bowie on many of his albums, was another who knew the singer was ill.
"His death was no different from his life -- a work of Art. He made 'Blackstar' for us, his parting gift," Visconti wrote on Facebook.
"I knew for a year this was the way it would be. I wasn't, however, prepared for it."
Highlighting how secret Bowie kept his illness, long-time collaborator and friend Brian Eno said his death came as "a complete surprise".
He told the BBC he received an email from Bowie a week before his death which he now believes was a farewell message.
"It was funny as always, and as surreal, looping through word games and allusions and all the usual stuff we did. It ended with this sentence: 'Thank you for our good times, Brian. they will never rot'," Eno said.
"I realise now he was saying goodbye."