Irish musician Sinead O'Connor died last year of "natural causes," a London coroner announced Tuesday.

The Grammy award-winning singer, best known for her 1990 cover of Prince ballad "Nothing Compares 2 U," was found unresponsive at her south London home last July, aged 56. 

At the time, London's Metropolitan Police said they were not treating her death as suspicious but an autopsy was still carried out to determine the cause of death.

Now, Southwark Coroner's Court in south London said in a statement: "This is to confirm that Ms. O'Connor died of natural causes" – meaning it was not linked to external forces.

"The coroner has therefore ceased their involvement in her death."

The life of Sinead O'Connor

O'Connor's death prompted an outpouring of sympathy from her legions of fans including other musicians and celebrities around the world, particularly in her homeland of Ireland.

Hundreds turned out to witness her funeral cortege in her former home town of Bray, 20 kilometers (13 miles) south of Dublin, including Irish Prime Minister Leo Varadkar and U2 frontman Bono.

O'Connor began her career singing on the streets of Dublin but rose to international fame in the 1990s. In addition to her music, she became known for her willingness to criticize the Catholic Church on issues such as sexual abuse, which saw her vilified by some and praised as a trailblazer by others. 

She also spoken publicly about her mental health, telling the US television host Oprah Winfrey in 2007 that she struggled with thoughts of suicide and had been diagnosed with bipolar disorder.

Before she died, she had been putting the final touches to a new album and planning a tour and movie based on her autobiography "Rememberings," according to her agent.

In her final months, she withdrew from the limelight after her son Shane took his own life in 2022, aged 17.

mf/rt (AFP, AP)