Heath Ledger by LRRB and Co./WireImage.com Heath Ledger by LRRB and Co./WireImage.com

In the wake of Heath Ledger's shocking death, the AP reports that an autopsy being conducted today is so far "inconclusive." Sources from the medical examiner's office say that more tests are needed, and it will be about 10 days before more details are known.

No illegal drugs were found in the actor's apartment, and a rolled-up $20 bill found near his body has tested negative for any trace of narcotics. Ledger, though, was in possession of six prescription medications, including pills to treat insomnia and anxiety, and an antihistamine, the AP reports. Three of the drugs were prescribed in Europe.

Ledger's passing has been described by his family as "accidental," police reported no obvious indications of suicide, and he was heard alive as late as 12:30 pm (three hours before he was found). Since his death, glowing remembrances of the 28-year-old actor have come to the fore. "He was really polite and nice," Paul Sevigny, the owner of a West Village club Ledger frequented, tells the New York Times, adding that amid a city of hard-partying troublemakers, Ledger "certainly wasn't one of them."

Within hours of the unsettling news, friends, onetime cast mates and other peers made statements fondly remembering Ledger. "I would give back all my awards to have him back," John Travolta told PageSix.com at a Tuesday event. "This whole evening has been really hard for me."

Director Ang Lee also spoke out about the loss, telling the AP, "Working with Heath was one of the purest joys of my life. He brought to the role of [ Brokeback Mountain's] Ennis more than any of us could have imagined. His death is heartbreaking."

While Ledger's ex-fiancée, Michelle Williams, is en route to New York City from Sweden (where she was lensing a movie), Naomi Watts, who dated Ledger for 16 months (until April 2004), has canceled all her appearances at the Sundance Film Festival.

Until more details about the cause of Ledger's death emerge, friends and family can only speculate on what went wrong. Ledger's uncle, Neil Bell, tells the Times, "He was in good spirits and having a wonderful time on this Terry Gilliam movie," The Imaginarium of Doctor Parnassus, which Heath was filming for a 2009 release.

Ledger's rep hopes to quell any hypothesizing, saying, "This is an extremely difficult time for his loved ones and we are asking the media to please respect the family's privacy and avoid speculation until the facts are known."

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