LONDON (AP) -- George Michael, the British pop superstar who reached early fame with WHAM! and went on to a solo career lined with controversies and chart-topping hits that blended soul and dance music with daring social and personal commentary, has died, his publicist said Sunday. He was 53.

Michael died at his home in Goring, England. His publicist, Cindi Berger, said he had not been ill. Michael's manager, Michael Lippman, says the cause of death was heart failure. His family issued a statement through Thames Valley Police saying that he "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."

Before Lippmann's announcement, police issued a statement calling the death "unexplained but not suspicious" and that "a post mortem will be undertaken in due course."

The loss of Michael continues a year of grief in the music industry, with David Bowie, Prince and Glenn Frey among those dying before age 70.

One of the giants of '80s and '90s music, and an early idol for the MTV generation, Michael enjoyed immense popularity from the start with hits such as "Wake Me Up Before You Go-Go," ''Young Guns (Go For It)" and "Freedom." As a solo artist, he developed into a more serious singer and songwriter, lauded by critics for his powerful vocal and expressive range. He sold well over 100 million albums globally, earned numerous Grammy and American Music Awards, and recorded duets with Aretha Franklin, Ray Charles, Luciano Pavarotti and Elton John among others.

"I have lost a beloved friend - the kindest, most generous soul and a brilliant artist," Elton John wrote on Instagram.

He reached the very heights of success, but agonized over being a celebrity. He spoke of cutting back on tours and interviews and letting his work speak for itself. One aging superstar thought he was behaving like a fool: In a public letter dated Sept. 9, 1990, Frank Sinatra advised Michael to "loosen up" and "swing, man."

"The tragedy of fame is when no one shows up and you're singing to the cleaning lady in some empty joint that hasn't seen a paying customer since Saint Swithin's day," Sinatra wrote.

Michael, with tailored good looks and an easy stage manner, formed the duo WHAM! with his school friend Andrew Ridgeley in the early 1980s. Helped by MTV, founded around the same time, easily crossed the Atlantic to become popular in the United States with Michael, as lead singer, usually the focal point.

He started his solo career shortly before WHAM! split, with the release of the megahit single "Careless Whisper," making a seamless transition. Critics generally viewed his WHAM! songs as catchy but disposable pop and gave his solo efforts far higher marks.

Throughout his career, his drug use and taste for risky sex brought him into frequent brushes with the law, most famously in 1998 when he was arrested for public lewdness in Los Angeles. Yet, he managed to turn the incident into fodder for a popular song that poked fun at his behavior, and his acknowledgment of his homosexuality at that time made him even more popular with his fans.