No illegal drugs in Winehouse's system

Amy Winehouse had no illegal drugs in her system when she died, and it is still unclear what killed the singer, her family said Tuesday, according to The Associated Press.

The family said in a statement that toxicology tests showed "alcohol was present" in the singer's body but it hasn't yet been determined if it contributed to her death.

The 27-year-old singer, who had battled drug and alcohol addiction for years, was found dead in her London home on July 23, and an initial post-mortem failed to determine the cause of death.

A statement released by spokesman Chris Goodman on the family's behalf said "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 statement did not mention whether any legal drugs were found.

It said the family awaited the outcome of an inquest that is due to begin Oct. 26. In Britain, inquests are held to establish the facts whenever someone dies violently or in unexplained circumstances.