The death of Amy Winehouse at her London apartment remains a mystery at this point.  

London Ambulance Service received a call at 3.54 pm local time.  When they arrived there, the 27-year-old award winning singer was already dead.  A spokeswoman for the London Ambulance Service said: Sadly the patient had died.

Her cause of death is not yet known.  However, the singer has struggled with depression, self-harm, and suicide over the past few years.  

Friends placed Amy Winehouse on suicide watch after she threatened to drive a knife into her chest in 2008 and asked, What's the point in living?

When she was 23 years old, Winehouse told Perez Hilton: Blake is the best man in the world. We would never ever harm each other... I was cutting myself after he found me in our room about to do drugs with a call girl and rightly said I wasn't good enough for him. I lost it and he saved my life.

The singer was notoriously disturbed and suffered from alcohol addiction, drug addiction, and severe mental health issues. Winehouse took herself out of a comeback tour last month after she appeared too drunk to perform.

Winehouse's drug abuse has been publicly documented. A video of the singer smoking crack cocaine appeared on YouTube in January 2008.

Winehouse's 2006 Back to Black album cemented her fame and won her five Grammy Awards.

Rumors of Winehouse's death began to appear on Twitter Saturday evening. Among those to comment was former prime minister's wife Sarah Brown.

BBC Radio 1 DJ Fearne Cotton wrote on Twitter, Can not believe the news. Amy was a special girl. The saddest news.

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