Friends of the 40-year-old singer, including movie star Jackie Chan, had flocked to her bedside after she was admitted to the Hong Kong Sanatorium and Hospital late on Monday.

A hospital spokeswoman said Mui was confirmed dead at 2:50 am on Tuesday morning, but did not give details.

Mui had kept a low profile since she sold out a eight-night concert run in Hong Kong that ended on November 15.

Her condition was reported to have worsened suddenly on Monday and she was rushed to hospital where she later slipped into a coma and died.

Hong Kong film legend Chan led emotional tributes to the singer, unable to hold back tears even after revealing that Mui had urged her legions of fans "to stay calm and not to cry for her."

Veteran entertainer Eric Tsang, a legend of Hong Kong's show business industry, paid tribute to Mui's courage in battling cancer to the end.

"Even though her condition deteriorated... she waited for all her best friends to come to her bedside so she could see them one last time, to wish them well before she was willing to leave them," Tsang said.

Mui ended weeks of intense media speculation by confirming on September 5 that she had been diagnosed with cervical cancer.

"I will win this battle. I won't disappoint my friends. I don't want my fans to cry anymore, to worry anymore. I am not a loser and a weakling even though I am a patient," Mui said then.

Her elder sister, Mui Oi-fong, died of ovarian cancer in April 2000 after a 15-year battle against the disease.

"I can't believe she's gone. (Leslie) Cheung Kwok-wing last year, now A-Mui. All the best singers we enjoyed listening to have died. She's still so young and beautiful," said Janie Siu, one of thousands of fans who rushed to music shops to snap up one of Mui's more than 30 albums released during her career.

Life-long Mui fan, James Yip Man-king, said: "There were few singers who could move an audience to tears like Mui Yim-fong... she was one of a kind, her songs were so meaningful. There can never be another like her."

Mui, known as the "Big Sister" of Hong Kong show business, began her singing career in 1968.

At the age of five she was singing Chinese opera and pop songs in theatres but her big break came in 1982 when she saw off 3,000 contestants to win the New Talent Singing Competition.

Mui went on to carve out a reputation as "the Madonna of Asia" with her outrageous costumes, raunchy stage performances and a stream of hits which netted her numerous awards and helped transcend the image of Chinese female singers.

But despite her sultry good looks and hordes of male admirers, Mui never married and often sang openly about her loneliness in her songs.

Mui's uniquely deep, haunting voice was used for the theme songs in dozens of films and shows and she remained phenomenally popular across Asia right up to her death.

The singer still holds the Hong Kong record for sold-out concerts when she played to capacity crowds for 28 consecutive nights during her heyday in the 1980s.

She later turned to acting and enjoyed success starring in films including the "Heroic Trio" and "Drunken Master 2".

Her portrayal of a tortured ghost in "Rouge" won her Taiwan's prestigious Golden Horse award in 1987. Last year she starred opposite Jackie Cheung in Ann Hui's acclaimed July Rhapsody.

But despite her glittering career, Mui said her biggest regret was not furthering her education, saying she would have preferred to have been a lawyer instead of a pop-star.