01/24/2008 at 08:00 AM EST
It will be days before authorities can determine the cause of Heath Ledger
's death, but more details have surfaced on what specific drugs were found in his room Tuesday.
The 28-year-old actor had six prescription drugs, including anti-anxiety medications and sleeping pills, unnamed police sources tell the Associated Press. (Ledger had openly discussed his problems sleeping
Police confirmed to PEOPLE earlier Wednesday that an undisclosed number of prescription drugs – and no illegal drugs – were found on the scene. New York Police Commissioner Ray Kelly confirmed in a press conference that a rolled-up $20 bill
was found in the room, but police say it tested negative for drug residue.
Also on Wednesday, the New York Times reported
that, of the six different types of prescription drugs in Ledger's apartment, three were prescribed in Europe, and noted that Ledger had recently returned from filming in London.
Further toxicology and tissue testing – after an inconclusive autopsy report
– to determine the cause of death could take 10 days to two weeks, the city medical examiner's office says.
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