Sinead O'Connor, singer of 'Nothing Compares 2 U,' dead at 56

Sinead O'Connor, the Irish singer known for her stirring voice, 1990 chart-topping hit "Nothing Compares 2 U" and outspoken views, has died at the age of 56, Irish media quoted her family as saying on Wednesday.

Brash and direct - her shaved head, pained expression, and shapeless wardrobe a direct challenge to popular culture's long-prevailing notions of femininity and sexuality – O'Connor irrevocably changed the image of women in music.

"It is with great sadness that we announce the passing of our beloved Sinead. Her family and friends are devastated and have requested privacy at this very difficult time," RTE quoted a statement from the singer's family as saying.

The circumstances of her death were unclear.

O'Connor crashed onto the global music scene with her mesmerizing version of "Nothing Compares 2 U", originally written by Prince and accompanied by a music video in which she faced directly into the camera and cried.

Known as much for her outspoken views on religion, sex, feminism and war as for her music, she will be remembered in some quarters for ripping up a photo of Pope John Paul II during a 1992 television appearance on "Saturday Night Live," declaring: "Fight the real enemy".

(With inputs from agencies)