(CBS/AP) LONDON – Police say an autopsy on singer Amy Winehouse has not established what killed her.

The Metropolitan Police said Monday that further toxicology tests are needed and the results are expected in two to four weeks.

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The singer died Saturday, at the age of 27, after publicly struggling with drug and alcohol abuse for 부산출장마사지 years. Her body was discovered at her London home by a member of her security team, who called an ambulance. It arrived too late to save her.

A coroner opened and adjourned an inquest into the unexplained death, leaving Winehouse’s family free to plan her funeral. A private family service could be held as early as Tuesday.

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An inquest into the singer’s death was opened and adjourned at London’s St. Pancras Coroner’s Court. During the two-minute hearing, an official read out the name, birth date and address of Winehouse, described as “a divorced lady living at Camden Square NW1.”

“She was a singer songwriter at the time of her death and was identified by her family here at St. Pancras this morning,” said coroner’s officer Sharon Duff.

Duff said the scene of Winehouse’s death “was investigated by police and determined non-suspicious.”

In Britain, inquests are held to establish the facts whenever someone dies violently or in unexplained circumstances. Assistant Deputy Coroner Suzanne Greenaway said Winehouse’s inquest would resume on Oct. 26.