Toxicology reports show Amy Winehouse had no illegal drugs in her body when she died and it's not clear what killed her, the singer's family said Tuesday.

Family spokesman Chris Goodman said although "alcohol was present, ... toxicology results returned to the Winehouse family by authorities have confirmed that there were no illegal substances in Amy's system at the time of her death."

"The family would like to thank police and coroner for their continuing thorough investigations and for keeping them informed throughout the process. They await the outcome of the inquest [into Winehouse's death] in October," Goodman said.

Winehouse was 27 years old when she was found dead in her London home July 23.

At her funeral, her father Mitch said the singer had been drug-free for years before her death but was struggling with alcohol addiction, MTV.com reported.

"Three years ago, Amy conquered her drug dependency, the doctors said it was impossible but she really did it. She was trying hard to deal with her drinking and had just completed three weeks of abstinence."

"She said, "Dad, I've had enough of drinking. I can't stand the look on your and the family's faces any more,"' Mitch Winehouse said. (c) UPI

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