Tributes poured in from the music world after British pop superstar George Michael, who rose to fame with the duo Wham! and a string of smash hits including “Last Christmas”, died aged 53.

Michael died of apparent heart failure on Christmas Day at his home in Goring, a village on the River Thames in Oxfordshire, west of London, after an award-winning career spanning more than three decades.

Big names in entertainment like Elton John and Madonna hailed Michael’s talent and human qualities, while former Wham! bandmate Andrew Ridgeley said he was “heartbroken at the loss of my beloved friend”.

Many tributes referred to the spate of deaths of famous musicians in 2016, including rock legend David Bowie in January, funk icon Prince in April and soulful folk singer Leonard Cohen in November.

“No, not George Michael as well. Another musical great leaves us this year. 2016 can just sod off,” Gary Lineker, football presenter and former England captain, said on Twitter.

Police said they would be conducting a post-mortem examination and were treating the death as “unexplained but not suspicious”.

His manager Michael Lippman told Billboard magazine that the cause of the star’s death was heart failure. “I’m devastated,” Lippman was quoted as saying, adding that he was told Michael had been found “in bed, lying peacefully”.

Flowers were placed outside his home in Goring, and candles were left outside his London home — a large mansion in Highgate, in the north of the capital.

Michael was due to release a documentary about his life in 2017 and producer and songwriter Naughty Boy, whose real name is Shahid Khan, was working with Michael on a new album for next year.