Two doctors, one in California and another in Texas, are being investigated by federal drug authorities over the death of Heath Ledger.

The 28-year old Australian actor was found dead in his New York apartment last month due to an accidental, but lethal cocktail of prescription drugs.

A source reveals to People: “We are investigating doctors in Los Angeles and Texas with regard to Ledger’s prescriptions.”

When asked if the doctors had done anything wrong, the source answered: “We don’t know yet. The agents were there this week, and we are waiting to hear from them.”

Stay tuned to Entertainmentwise for more on this story.