Brokeback Mountain star Heath Ledger found dead in New York

Michelle Williams, the former fiancee of actor Heath Ledger, and mother of his two-year-old daughter, was flying home to New York today after learning of the Australian-born actor's mysterious death. Ledger, 28, best known for his Oscar-nominated role as one of two cowboys in the 2005 film, Brokeback Mountain, was found dead at a downtown Manhattan apartment yesterday.

"He was found unconscious at the apartment and pronounced dead," said a spokesman for New York Police Department, where it is understood detectives are investigating the possibility that he died of a drug overdose. Early television reports said his body had been found at the apartment on Broome Street in SoHo surrounded by pills. Police said they did not suspect foul play.

The Perth-born actor split up with Williams in September. They had met in 2004 while filming Brokeback Mountain, in which she played the woman Ledger's character Ennis eventually married (pictured). "I remember being in rehearsal, and the two of them had googly eyes with each other," Jake Gyllenhaal, who played the other cowboy, Jack, once said of the couple. "There were sparks immediately," added co-star Anne Hathaway. "It was adorable." Ledger and Williams were together for three years and had a daughter, Matilda, before they broke up. Williams was shooting her new film Mammoth in Sweden when she received the news about her ex-boyfriend's death. (Continued below)

Ledger had only recently left London where he was filming the new Terry Gilliam film, The Imaginarium of Doctor Parnassus. He also plays the Joker in the next Batman film, The Dark Knight. He recently appeared as one of the six 'Bob Dylans' in the film I'm Not There, for which his co-star and fellow Aussie Cate Blanchett was today nominated for the best supporting actress Oscar.

But it will be for his ground-breaking role in Ang Lee's brilliant Brokeback Mountain, based on the story by E Annie Proulx about a forbidden and secretive relationship between two Wyoming ranch hands, that he will be best remembered. Like Gyllenhaal, he took a huge risk to play a role which there was never any guarantee cinema audiences would accept.

But Lee's direction, and the lead actors' sensitive performances, ensured its success. Rolling Stone magazine said on the film's release: "Ledger's magnificent performance is an acting miracle. He seems to tear it from his insides. Ledger doesn't just know how Ennis moves, speaks and listens; he knows how he breathes. To see him inhale the scent of a shirt hanging in Jack's closet is to take measure of the pain of love lost."