"Inquiries continue into the circumstances of the death," police said in a statement. "At this early stage it is being treated as unexplained and there have been no arrests in connection with the incident."
The 27-year-old singer, best known for her song "Rehab," was found dead Saturday in her London home. Although Winehouse had a longstanding history with drug abuse, police are making it clear that the cause of death is still unknown.
"I am aware of reports suggesting this death is the result of a suspected drugs overdose, but would like to re-emphasize that no post-mortem has yet been done and that it would be inappropriate to speculate on the cause of death," Metropolitan Police Superintendent Raj Kohli said.
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On Sunday, Winehouse's management company Metropolis Music issued a statement. "We are trying to come to terms with the death of a dear friend and colleague, the most amazing artist and talent," it read. "We will always remember Amy as a vibrant, funny, caring young woman who made everyone around her feel welcome. We have lost a very special person, part of our family."