Award-winning British pop singer George Michael has died at age 53, his publicist Cindi Berger said Sunday.

Michael, born Georgios Kyriacos Panayiotou, rose to fame in the 1980s and 1990s as a member of the pop duo Wham! He collaborated with major recording artists including Aretha Franklin, Ray Charles, Elton John, and Luciano Pavarotti -- selling more than 100 million records and amassing numerous Grammy and American Music Awards over a three decade career.

Michael died at his property in Goring, Oxfordshire, England. Thames Valley Police said there were no suspicious circumstances.

The pop star’s death shocked his fans and music industry peers. He was widely believed to be in good health and was said to be working on new material as recently as 10 days ago.

“There was absolutely no indication that he was in any sort of ill health. This comes as a real surprise,” music journalist Alan Cross told CTV News Channel. “You can bet that this is going to be tabloid fodder for some time.”

Michael had seven number one singles in the U.K. and eight number one hits on the Billboard Hot 100.

Michael was partnered with Andrew Ridgley in Wham! They skyrocketed to fame in the early 1980s thanks to the duo’s youthful good looks and fun-loving stage manner, as well as the emerging popularity of music videos on MTV.

The group’s best-known singles included "Freedom", "Everything She Wants", and "Careless Whisper," which reached number one in nearly 25 countries, including the UK and U.S.

Their 1984 holiday hit “Last Christmas,” which was written and produced by Michael, continues to be widely played and covered by other artists. The song spent 13 weeks at number two on the UK Singles Chart in 1985.

“Wham! was always a cultural touchstone for so many people. George Michael was a tremendous talent,” said Cross.

Wham! became the first western pop act to perform in China in 1985, beating out other hopefuls like Queen and the Rolling Stones. China had just emerged from the tumultuous Cultural Revolution, and many government officials were concerned the flamboyant stage act would disrupt the famously rigid social atmosphere.

However, Chinese desire to attract foreign investment trumped social reservations. Michael and Ridgley were allowed to perform hits like “Wake Me Up Before You Go-Go” in a region where many musical genres were banned.

“At that point, China was still a very closed country to western interests,” said Cross. “Wham! became the first western pop act to actually make some inroads in the country.”

Michael launched his solo career following the group’s break-up in 1987 with his first solo album, 1987's "Faith." Then came a collaboration with American soul music legend Aretha Franklin. The Grammy award-winning song “I Knew You Were Waiting (For Me)” reached number one on both the U.S. Billboard Hot 100 and U.K. Singles Chart that year.

In 1987, Michael’s provocative single “I Want Your Sex” was banned by the BBC. The accompanying music video featuring Michael's then-girlfriend Kathy Jeung writhing on a bed, with a Spanish model standing in for blurred nude scenes. It received wide play on MTV which in 2002 ranked it at number three in its countdown show “Most Controversial Videos Ever to Air on MTV.”

Michael’s personal life made headlines throughout his career. Questions about the pop icon’s sexual orientation reached a fever pitch following his 1998 arrest by an undercover male police officer for “engaging in a lewd act” in a California public restroom. He would later speak openly about struggling to define his sexuality as a gay man.

Michael was an admitted user of marijuana and prescription sedatives and several times was found slumped over his car's steering wheel after using both at the same time. He drove his Land Rover into the side of a store in 2010, resulting in a five-year suspension of his license.

In October 2011, he cancelled a performance at London's Royal Albert Hall due to a viral infection. He was also hospitalized in Vienna one month later after complaining of chest pains. It was later confirmed the singer was suffering from pneumonia and he was placed in an intensive care unit. Remaining performances were cancelled or postponed.

In December 2011, Michael made a speech outside his London home and announced he had undergone a tracheotomy. He said he had developed a temporary “West Country” accent after waking from a coma.

Police are awaiting the results of an autopsy before commenting further on the circumstances of Michael’s death.

“Thames Valley Police were called to a property in Goring-on-Thames shortly before 2 p.m. Christmas Day. Sadly, a 53-year-old man was confirmed deceased at the scene,” said the police in a statement Sunday. “At this stage the death is being treated as unexplained but not suspicious. A post mortem will be undertaken in due course.”

No other details were released.

Michael was nominated for the Songwriters Hall of Fame in October. A documentary film said to feature unseen archival footage and interviews is set to be released in March 2017.

With files from The Associated Press