Two doctors are under investigation in connection with prescriptions disbursed to actor Heath Ledger before he died, Access Hollywood has learned.
"The investigation is proceeding aggressively and can conclude from as soon as one day or several weeks," a DEA source told Access.
According to People magazine, the doctors are located in California and Texas.
"We are investigating doctors in Los Angeles and Texas with regard to Ledger’s prescriptions," a source tells People.
The source could not confirm to People if any wrongdoing was involved in the investigation, saying, "We don’t know yet. The agents were there this week, and we are waiting to hear from them."
The doctors involved in the investigation are believed to have supplied Ledger with Oxycontin and Vicodin, according to law enforcement sources, as reported by New York's Daily News.
The investigation aims to find out if the painkillers were prescribed to Ledger legally, says the Daily News.
Ledger was found dead in his New York City apartment on January 22. An autopsy concluded a mixture of prescription drugs caused his death.