Authorities close Ledger case

Federal prosecutors have closed an investigation into the death of Heath Ledger, reports People.

An unnamed law enforcement source claimed that the US Attorney's Office will not enforce a subpoena issued against actress Mary-Kate Olsen, who earlier refused to speak with authorities unless she was granted immunity from prosecution.

Olsen was reportedly the first person that Ledger's masseuse called when she found the actor's body in his New York apartment.

The probe has now been closed without any charges being filed.

Ledger's death was ruled as an accidental overdose from prescription drugs, including painkillers oxycodone and hydrocodone.