Toxicology results show there were “no illegal substances” in Amy Winehouse’s body at the time of her death, her family said today.

The Back to Black singer was found dead at her flat in north London on July 23.

The family statement 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

“Results indicate that alcohol was present but it cannot be determined as yet if it played a role in her death.

“The family would like to thank the police and coroner for their continuing thorough investigations and for keeping them informed throughout the process. They await the outcome of the inquest in October.”

An initial post-mortem examination proved inconclusive and an inquest was opened and adjourned with no cause of death given for the 27-year-old star.

The inquest, at St Pancras Coroner’s Court, is due to be re-opened on October 26.

Because of Winehouse’s very public battles with drink and drugs, news of her death was quickly followed by suggestions it could be related to one or the other.

Her father Mitch Winehouse told mourners at her funeral his daughter had been the happiest she had been in a long time in the weeks before her death.

He said she had “conquered” her drug addiction and was “trying hard to deal with her drinking”.

In a heartfelt eulogy, Mr Winehouse said his daughter had recently “completed three weeks of abstinence” adding she had told him: “Dad I’ve had enough of drinking, I can’t stand the look on your and the family’s faces any more.”

At the funeral service at Edgwarebury Cemetery in north London, Mr Winehouse said: “She was the happiest she has been for years. We all remember that great night at the 100 Club on Oxford Street, her voice was good, her wit and timing were perfect. She told me that she had ‘thoroughly, thoroughly enjoyed herself’.

He added: “But knowing she wasn’t depressed, knowing she passed away, knowing she passed away happy, it makes us all feel better.”

Mr Winehouse has also revealed plans to set up a foundation in his daughter’s name to help people struggling with addiction.