Tests on a rolled-up $20 bill found near Heath Ledger's bed detected no drug residue, the New York Police Department said Wednesday.

Discovery of the bill had raised the prospect that Ledger might have been snorting drugs, but the negative test diminished that possibility. A preliminary autopsy on Ledger's body Wednesday was inconclusive.

Authorities found six different types of prescription drugs in Ledger's apartment, including pills to treat insomnia and anxiety and an antihistamine, according to two law enforcement officials who spoke on condition of anonymity because the investigation is ongoing. Three of the drugs were prescribed in Europe.

Ledger was found dead in his New York City apartment Tuesday. The medical examiner's office in New York said early Wednesday that an autopsy on Ledger was inconclusive, and more tests are needed.

A spokeswoman for the office, Ellen Borakove, said that it will take about 10 days to complete toxicological tests on tissue samples taken from Ledger's body.

Prior to the autopsy, police said the death of the 28-year-old Australian actor was caused by a possible drug overdose and appeared to be accidental. There were sleeping pills nearby Ledger's body, police said.

Police also on Wednesday provided an in-depth timeline of Ledger's final moments.

They said a maid had been in the actor's bedroom moments before he died. She'd found him asleep. Later his massage therapist tried to wake him and found him unresponsive and cold to the touch.

She made a frantic call to Ledger's friend, actress Mary Kate Olsen, who said she would send her security guards. The masseuse then called 911. She was given guidance on CPR, but it was too late.

Ledger's Family Speaks

Appearing before cameras in Australia on Tuesday, Ledger's family maintained that the actor's death was an accident.

His father, Kim, read a statement to reporters, describing his son as a "down-to-earth, generous, kind-hearted, life-loving, unselfish individual" who was "extremely inspirational to many."

"Heath has touched so many people on so many different levels during his short life but few had the pleasure of truly knowing him," Kim Ledger said. "Please now respect our family's need to grieve and come to terms with our loss privately."

Ledger's publicist, Mara Buxbaum, asked the media in a statement Tuesday night to avoid speculation.

"We are all deeply saddened and shocked by this accident," Buxbaum said. "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."

Ledger split last year with Michelle Williams, who played his wife in the film "Brokeback Mountain." The two had a daughter, the now 2-year-old Matilda, and lived together in Brooklyn.

Early Wednesday, Williams and Matilda left Trollhattan, Sweden, where the 27-year-old actress had been shooting scenes for the upcoming film "Mammoth," said Martin Stromberg, a spokesman for film production company Memfis Film.

"She received the news at her hotel late last night," Stromberg said, adding he had not spoken to the actress after she learned of Ledger's death.

Recent Roles Got To Ledger

The actor, who was nominated for an Oscar for his role in "Brokeback Mountain," told The New York Times in a November interview that he had "stressed out a little too much" while playing an incarnation of Bob Dylan in the film "I'm Not There."

And with "The Dark Knight" -- the upcoming "Batman Begins" sequel that stars Ledger as the legendary character The Joker -- the actor said the role of the "psychopathic, mass-murdering, schizophrenic clown with zero empathy" caused him to lose sleep.

"Last week I probably slept an average of two hours a night," Ledger told the newspaper. "I couldn't stop thinking. My body was exhausted, and my mind was still going." He said he took two Ambien pills, which only worked for an hour, the paper said.

Alan Horn, president and COO of "The Dark Knight" studio Warner Bros., and Jeff Robinov, president of the Warner Bros. Pictures Group, issued a statement on the death Tuesday afternoon.

"The studio is stunned and devastated by this tragic news," said Horn and Robinov. "The entertainment community has lost an enormous talent. Heath was a brilliant actor and an exceptional person. Our hearts go out to his family and friends."

Ledger was currently at work in director Terry Gilliam's fantasy film "The Imaginarium of Doctor Parnassus." There is no word on the future of the production. The actor previously worked with Gilliam on the 2005 fantasy adventure "The Brothers Grimm."

Mel Gibson, who played Ledger's vengeful father in the American Revolution action drama "The Patriot" in 2000, lamented the loss of Ledger in a statement.

"I had such great hope for him," Gibson said. "He was just taking off and to lose his life at such a young age is a tragic loss."

Ledger's breakthrough role in Hollywood came in 1999 at age 19, where he starred opposite Julia Stiles in "10 Things I Hate About You" -- a modern interpretation of Shakespeare's "The Taming of the Shrew."

After the film, Ledger resisted similar teen romantic comedy roles, opting for films like "The Patriot," the tragic drama "Monster's Ball" and Western biopic "Ned Kelley."

Bush Cancels Event In Light Of Tragedy

In Washington, Ledger's death has even affected President George W. Bush.

The White House has postponed Wednesday's event where Bush was going to promote an ad campaign aimed at preventing prescription drug abuse.

White House press secretary Dana Perino said that they thought it would be better to postpone the event "rather than run the risk of anyone thinking that we were being opportunistic in highlighting the issue" because pills were found by Ledger's body.

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