Tests conducted on a rolled-up $20 bill found near Heath Ledger's body detected no residue of drugs, New York City Police said Wednesday.
NYPD Commissioner Ray Kelly said earlier Wednesday that the way the bill was folded indicated it could have been used for drugs, though there was no visible residue on it and no illegal drugs were found in Ledger's apartment.
Photo Essay: Mourning Heath Ledger
TMZ.com reported that the bill had a powdered substance on it, citing NYPD sources; CBS 2 in New York City reported that cops found drug packets along with the $20 bill in Ledger's apartment.
An autopsy performed on the Oscar-nominated "Brokeback Mountain" actor Wednesday was inconclusive, and more tests are needed, the New York City Medical Examiner's Office said.
A spokeswoman for the office, Ellen Borakove, said it will take about 10 days to complete the investigation.
Police said they found bottles of prescription sleeping pills and anti-anxiety medication in his bedroom and in the bathroom; there were still pills in the bottles.
Authorities discovered six different types of prescription drugs in Ledger's apartment, including the pills to treat insomnia and anxiety as well as 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.
Police have said Ledger could have died from a possible drug overdose, but his death appeared to be accidental.
The 28-year-old Australia-born actor's ex-fiancée, 27-year-old actress Michelle Williams, was flying to New York from Sweden with their 2-year-old daughter, Matilda, her father said.
"It has just broken everybody's heart in my family," Larry Williams, Michelle's dad, told The Daily Telegraph in Australia. "My heart goes out to everyone, his family, my family, we are just very saddened. The saddest thing is his daughter, whom he just loved dearly."
Ledger was found dead Tuesday at his downtown Manhattan residence, face-down and naked in his bed with prescription sleeping pills in the apartment, police said.
Ledger's father, Kim Ledger, released a statement on Australian television while surrounded by his family:
"We, Heath's family, confirm the very tragic, untimely and accidental passing of our dearly loved son, brother and doting father of Matilda. He was found peacefully asleep in his New York apartment by his housekeeper at 3:30 p.m. U.S. time.
"We would like to thank our friends and everyone around the world for their well wishes and kind thoughts at this time. Heath has touched so many people on so many different levels during his short life but few had the pleasure of truly knowing him.
"He was a down-to-earth, generous, kind-hearted, life-loving and selfless individual who was extremely inspirational to many. Please now respect our families need to grieve and come to terms with our loss privately."
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Ledger's publicist, Mara Buxbaum, also made a statement Tuesday night asking for privacy.
"We are all deeply saddened and shocked by this accident. 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."
Ang Lee, who directed Ledger in "Brokeback Mountain," said "working with Heath was one of the purest joys of my life."
"He brought to the role of Ennis more than any of us could have imagined — a thirst for life, for love and for truth, and a vulnerability that made everyone who knew him love him. His death is heartbreaking," Lee said.
Ledger was found at his apartment at 421 Broome Street in the SoHo section of New York City and was pronounced dead at 3:35 p.m. EST, NYPD spokeswoman Stephanie Jaramillo told FOXNews.com.
The actor had an appointment for a massage at the residence in the tony SoHo neighborhood, NYPD spokesman Paul Browne said. A housekeeper who went to let him know the masseuse had arrived and the massage therapist found his naked body in the bed at about 3:30 p.m. They tried to revive him, but he was already dead.
Ledger's housekeeper, Teresa Solomon, arrived at his apartment with her own key and let herself in. At 1 p.m., she went to his bedroom to change a light bulb, and saw Ledger sleeping and heard him snoring. She left the room without thinking anything was wrong.
At 2:45 p.m., a masseuse named Diana Wolozin showed up for her massage appointment with Ledger, who didn't answer when she knocked on his door.
She then tried to call him on his cell phone, but again got no response. She went into the bedroom, set up her massage table and again tried to wake Ledger.
Wolozin told police that Ledger was cold to the touch, but she just assumed he was unconscious. She proceeded to grab his cell phone and call Mary Kate Olsen, whose number is programmed into the phone. Wolozin knew that Olsen and Ledger were friends, and she asked Olsen for advice on what she should do next.
Olsen, who also lives in Manhattan but was in California at the time, responded by saying she would send over her private security guards to help deal with the situation. In the ensuing moments, Wolozin realized that Ledger might be dead, and called 911.
The emergency operator provided Wolozin directions on how to do CPR, but it was too late.
Paramedics arrived minutes later — at about the same time as Olsen's security guards.
Bottles of the generic forms of Xanax and Valium, both anti-anxiety drugs prescribed in his name, were found in the house, law-enforcement sources told the New York Post. The sleeping pill Ambien was also discovered near his body, the sources said.
Found on his nightstand, sources told the Post, was a bottle of Donormyl, an antihistamine used as a sleep aid and a packet of the drug Zopiclone, also used for insomnia.
The actor had pneumonia at the time of his death, TMZ.com reported.
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Wednesday morning, near the front entrance to Ledger's three-bedroom SoHo apartment, about two dozen bouquets of flowers and a dozen candles formed a makeshift memorial to the actor.
One note said, "I couldn't find anything bad about you."
Tuesday night, paparazzi and gawkers gathered, and several police officers put up barricades to control the crowd of about 300. Onlookers craned their necks as officers brought out a black body bag on a gurney, took it across the sidewalk and put it into a white medical examiner's office van.
As the door opened, bystanders snapped pictures with camera phones, rolled video and said, "He's coming out!"
The superintendent of the building, Tamba Mossa, told reporters that Ledger had lived there for four or five months, and that he recently "looked sad."
"I'm very, very sad. I wasn't prepared to hear about his death at that moment. He was a very great man," Mossa said.
The actor was nominated for an Oscar for his performance as a gay cowboy in "Brokeback Mountain," where he met his former fiancée, "Dawson's Creek" actress Williams, in 2005. Ledger and Williams had Matilda and lived in Brooklyn until they split up last year.
Ledger was often seen with Matilda in his new Manhattan neighborhood, where he used to shop at a home and children's store.
Michelle Vella, an employee there, said she had frequently seen Ledger with his daughter — carrying the toddler on his shoulders, or having ice cream with her.
"It's so sad. They were really close," said Vella. "He's a very down-to-earth guy and an amazing father."
"It's a shock; he's so young," said Taren Dolbashian, who also had seen Ledger with his daughter. "He always seems so happy."
Ledger most recently appeared in "I'm Not There," in which he played one of the many incarnations of Bob Dylan.
WJW FOX 8 News in Cleveland interviewed Ledger in Nov. 2007 when he was promoting "I'm Not There." In the interview, he told FOX: "Being a dad changes your perspective — I don't want to die young."
Ledger also told The New York Times in a November interview that he "stressed out a little too much" during the Dylan film, and had trouble sleeping while portraying the Joker, whom he called a "psychopathic, mass-murdering, schizophrenic clown with zero empathy."
"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.
His other roles include the suicidal son of Billy Bob Thornton in "Monster's Ball," a heroin addict in the 2006 Australian film "Candy" and starring turns in "A Knight's Tale" and "The Patriot."
Mel Gibson, Ledger's co-star in "The Patriot," said in a statement: "I had such great hope for him. He was just taking off and to lose his life at such a young age is a tragic loss. My thoughts and prayers are with him and his family.”
Ledger finished filming his role as the Joker this year in "The Dark Knight," a sequel to 2005's "Batman Begins."
In what may be his final finished performance, Ledger proved that he wouldn't be intimidated by taking on a character as iconic as Jack Nicholson's Joker. Ledger's version of the "Batman" villain, glimpsed in early teaser trailers, made it clear that his Joker would be more depraved and dark.
Curiosity about Ledger's final performance will likely stoke further interest in the summer blockbuster. "Dark Knight" director Christopher Nolan said earlier this month that Ledger's Joker would be wildly different from Nicholson's.
"It was a very great challenge for Heath," Nolan said. "He's extremely original, extremely frightening, tremendously edgy. A very young character, a very anarchic presence that taps into a lot of our basic fears and panic."
Michael Bodey, film reporter for The Australian, told FOXNews.com that in Australia, it is "equal parts shock and dismay, a waste of talent."
“He was one of the most interesting and intriguing actors to interview. He was a talented actor only now beginning to hit his stride ... Hollywood got a hold of him too early and tried to make him into something he didn’t want to be."
Before settling down with Williams, Ledger had relationships with actresses Heather Graham and Naomi Watts. He met Watts while working on the Western epic film "Ned Kelly" in 2002. The pair dated until 2004.
Ledger was born in 1979 in Perth, in western Australia, to a mining engineer and a French teacher, and got his first acting role playing Peter Pan at age 10 at a local theater company. He began acting in independent films as a 16-year-old in Sydney and played a cyclist hoping to land a spot on an Olympic team in a 1996 television show, "Seat."
After several independent films, Ledger moved to Los Angeles at age 19 and co-starred opposite Julia Stiles in "10 Things I Hate About You," a teen comedy reworking of "The Taming of the Shrew."
While not a marquee movie star, Ledger was a respected, award-winning actor who took his craft seriously rather than cashing in on his heartthrob looks.
Offers for other teen flicks came his way, but Ledger turned them down, preferring to remain idle than sign on for projects he didn't like.
"It wasn't a hard decision for me," Ledger told The Associated Press in 2001. "It was hard for everyone else around me to understand. Agents were like, 'You're crazy,' my parents were like, 'Come on, you have to eat."'
The Associated Press contributed to this report.