Heath Ledger died of an accidental overdose of prescription drugs, a US medical examiner has found.The Australian actor was found dead in his rented New York apartment on January 22 with prescription sleeping pills and anti-anxiety medicine drugs nearby."Mr Heath Ledger died as the result of acute intoxication by the combined effects of oxycodone, hydrocodone, diazepam, temazepam, alprazolam, and doxylamine," the the New York City medical examiner's office office said in a statement.The 28-year-old's family has arrived back in Perth where the funeral is due to be held.Details of funeral arrangements for the late co-star of Brokeback Mountain have not been announced, and the mother of his two-year-old daughter Matilda, actress Michelle Williams, has requested privacy.According to local media, the actor will be buried in the Ledger family plot near his grandparents.In a death notice placed in The West Australian newspaper, Mr Ledger's family rememberer him as "the most amazing ' old soul ' in a young man's body.""As a close knit and very private family we have observed you so determined yet quietly travelling your self-styled path in life, nothing would get in your way ... no mountain too tall, no river too wide," said the notice, which the newspaper said had been submitted by Ledger's relatives. It added: "Our hearts are broken."© Independent Television News Limited 2008. All rights reserved.