A documentary about the singer is set to be released on Saturday.

Irish singer and activist Sinéad O’Connor has died at the age of 56.

Her family announced the news “with great sadness”, saying “her family and friends are devastated”. The cause of death has not been made public.

She was best known for her single “Nothing Compares 2 U”, released in 1990, which reached number one and brought her worldwide fame.

Taoiseach (Irish PM) Leo Varadkar said her music “was loved around the world and her talent was unmatched”.

Irish President Michael D Higgins praised O’Connor’s “authenticity” as well as her “beautiful, unique voice”.

“What Ireland has lost at such a relatively young age is one of our greatest and most gifted composers, songwriters and performers of recent decades, one who had a unique talent and extraordinary connection with her audience, all of whom held such love and warmth for her,” he said.

Belfast filmmaker Kathryn Ferguson, one of the last few people to speak to O’Connor before her death, said she was “devastated” by the news.

Ferguson had been working on a documentary film about O’Connor, titled Nothing Compares, which is set to be released this Saturday.

“Our film really, for me, it was a love letter to Sinéad. It was made over many, many years,” she told BBC Radio 4’s Front Row. “And made because of the impact she’d had on me as a young girl growing up in Ireland.

“She is one of the most radical, incredible musicians that we’ve had. And we were very, very lucky to have had her.”

Social media was also flooded with tributes to the singer after her death was announced on Wednesday evening.

Singer Alison Moyet said O’Connor had an “astounding presence” and a voice that “cracked stone with force by increment”.

“As beautiful as any girl around & never traded on that card. I loved that about her. Iconoclast.”

Irish comedian Dara O’Briain said of her death: “That’s just very sad news. Poor thing. I hope she realised how much love there was for her.”

Musician Tim Burgess of the Charlatans said: “Sinead was the true embodiment of a punk spirit. She did not compromise and that made her life more of a struggle. Hoping that she has found peace.”

Irish author Marian Keyes described O’Connor’s death as “heartbreaking”.

“How she suffered. Poor, poor Sinéad. Rest in peace, you amazing, brave, beautiful, unique wonder.”

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