(CNN) -- Heath Ledger died from an accidental overdose of prescription medications including painkillers, anti-anxiety drugs and sleeping pills, the New York City medical examiner's office said Tuesday.
Actor Heath Ledger, 28, died January 22 at an apartment in Lower Manhattan.
"Mr. Heath Ledger died as the result of acute intoxication by the combined effects of oxycodone, hydrocodone, diazepam, temazepam, alprazolam, and doxylamine," the office said in a short statement.
"We have concluded that the manner of death is accident, resulting from the abuse of prescription medications."
Ledger died January 22 at an apartment in Lower Manhattan. The Oscar-nominated Australian actor, best known for his role as a stoic, closeted cowboy in the 2005 film "Brokeback Mountain," was 28.
An autopsy done on the actor January 23 was inconclusive.
A housekeeper, identified as Teresa Solomon, arrived at the apartment about 12:30 p.m. on the day Ledger died, a police source with knowledge of the investigation said.
She saw Ledger lying on a bed face down with a sheet pulled up around his shoulders and heard him snoring, the source said.
Masseuse Diana Wolozin arrived at the apartment about 2:45 p.m. to give Ledger a massage, according to the police source. About 15 minutes later, when he had not come out of the bedroom and the door remained closed, she went in, saw him lying in bed and set up a massage table.
She shook Ledger, but he did not respond, so she used his cell phone to call actress Mary-Kate Olsen, a friend of Ledger's, in California, the source said.
Olsen reportedly told her that she would call private security people in New York.
At 3:26 p.m., Wolozin called 911 and told authorities Ledger was not breathing. While on the phone with dispatchers, Wolozin tried to perform cardiopulmonary resuscitation on Ledger, but he was unresponsive.
Emergency personnel arrived seven minutes later, according to the police source, at about the same time as a private security person summoned by Olsen.
The medical technicians performed CPR on Ledger and used a cardiac defibrillator, but their efforts were in vain and he was pronounced dead at 3:36 p.m. By then, two other private security people summoned by Olsen had arrived as well as police.
Ledger's family called his death "very tragic, untimely and accidental." Relatives returned home Tuesday to Perth, Australia, where a private funeral ceremony reportedly will be held, according to The Associated Press. The timing of the funeral is unclear, the AP said.
His former fiancée, actress Michelle Williams, has asked the public to respect the need for her, the couple's 2-year-old daughter, Matilda, and others "to grieve privately."
"My heart is broken," Williams said in a statement issued last week via her publicist. "I am the mother of the most tender-hearted, high-spirited, beautiful little girl who is the spitting image of her father. All that I can cling to is his presence inside her that reveals itself every day. His family and I watch Matilda as she whispers to trees, hugs animals, and takes steps two at a time, and we know that he is with us still. She will be brought up in the best memories of him."
Condolences poured in from Ledger's friends and co-stars.
"He was a wonderful guy, he was a wonderful actor, he had a wonderful future ahead of him, and I liked him," said actor Eric Roberts, who worked with Ledger in "The Dark Knight," the latest installment in the "Batman" series set to open in July.
Colleagues on the Terry Gilliam's film "The Imaginarium of Doctor Parnassus," which Ledger had been shooting in England, said the actor apparently had been suffering from a respiratory ailment in the days before he died.
Christopher Plummer told Entertainment Weekly that Ledger had a "terrible, lingering bug in London, and he couldn't sleep at all. We all -- I thought he'd probably got walking pneumonia."
Ledger's first American film was the teen comedy "10 Things I Hate About You" in 1999. He passed up several scripts before taking a role in the Revolutionary War drama "The Patriot" in 2000 and "A Knight's Tale" in 2001. He also played a supporting role in "Monster's Ball."
But Ledger was perhaps best known for his portrayal of Ennis Del Mar in "Brokeback Mountain," Ang Lee's film about two cowboys who had a secret Romantic relationship. The role earned Ledger a best actor Oscar nomination.