Heath Ledger by Chris Weeks/WireImage.com Heath Ledger by Chris Weeks/WireImage.com

The federal government is getting involved in Heath Ledger's death. Law enforcement officials confirm exclusively to TVGuide.com that the Drug Enforcement Administration has launched an investigation into how Ledger obtained the multiple prescription drugs that led to his accidental overdose. According to the officials, the DEA has requested copies of Ledger's autopsy as well as the original police report from the crime scene.

A statement issued Wednesday morning by the Office of the New York City medical examiner declared Ledger's death "the result of acute intoxication by the combined effects of oxycodone, hydrocodone, diazepam, temazepam, alprazolam and doxylamine," and concluded the manner of death an "accident resulting from the abuse of prescription medications."

Ledger's father Kim responded with a statement saying, "We remain humble as parents and a family, among millions of people worldwide who may have suffered the tragic loss of a child. Few can understand the hollow, wrenching and enduring agony parents silently suffer when a child predeceases them. Today's results put an end to speculation, but our son's beautiful spirit and enduring memory will forever remain in our hearts.

"While no medications were taken in excess, we learned today the combination of doctor-prescribed drugs proved lethal for our boy. Heath's accidental death serves as a caution to the hidden dangers of combining prescription medication, even at low dosage."

Though Heath is now gone, his family says, "We treasure our beautiful granddaughter Matilda as well as an unbelievably wonderful network of close friends, forever, around the world. Families rarely experience the uplifting, warm and massive outpouring of grief and support as have we, from every corner of the planet. This has deeply and profoundly touched our hearts and lives. We are eternally grateful."

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