Hollywood film star Heath Ledger died from an accidental overdose of prescription drugs, a US medical examiner has confirmed.

His death was due to ‘acute intoxication’ by the combined effects of six different drugs – ibuprofen, painkiller OxyContin, anti-anxiety medication Xanax and Valium, and sleeping pills Restoril and Unisom.

The Brokeback Mountain star was found dead in his New York apartment on January 22. He was 28.

Michelle Williams, his former girlfriend and Brokeback Mountain co-star, has arrived in Heath’s native Australia for the actor’s funeral with their two-year-old daughter, Matilda.

Dressed in black, Michelle carried her daughter into the Perth airport terminal after arriving from New York.

Heath’s parents and other close relatives arrived in Perth on Tuesday after spending nearly two weeks in the US immediately after his death.

Family members attended a memorial ceremony in Los Angeles at the weekend, but have kept funeral arrangements a closely guarded secret.