Amy Winehouse's Autopsy Results Fail to Establish Cause of Death

07/25/2011 at 03:30 PM EDT

There is plenty of buzz over the question of how Amy Winehouse died, but the answer will not be known for some time to come.

According to reports, police say the late singer's autopsy – which took place on Monday at the St. Pancras Mortuary in London – has not established a cause of death. Results are expected in two to four weeks, after further toxicology tests are performed.

Shortly after her death, a police source told PEOPLE that the troubled Grammy winner, 27, was not surrounded by drugs or paraphernalia when she passed away.
– Dahvi Shira

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