It’s been six months since Matthew Perry‘s shocking death — and now, authorities have launched a criminal investigation into how the beloved Friends star obtained the ketamine that ultimately killed him.

Perry was immediately declared dead by paramedics after an assistant found him face down in his hot tub on Oct. 28, 2023. An autopsy report later revealed he died from the “acute effects of ketamine,” along with contributing factors such as “drowning, coronary artery disease and the effects of buprenorphine (used to treat opioid use disorder).” At the time, his death was ruled an accident.

However, the Los Angeles Police Department and the Drug Enforcement Administration are now looking into how the actor received the drug.

People close to Perry reportedly told the coroner’s investigators that he had been undergoing ketamine infusion therapy, which is often used to treat anxiety, depression, drug and alcohol problems, and more. But because his final treatment was more than a week before his death, the high levels of ketamine in his system at the time he died did not match up.

“The ketamine in his system at death could not be from that infusion therapy since ketamine’s half-life is three to four hours or less,” the autopsy report states, per The Hollywood Reporter.

This wouldn’t be the first time someone has been charged with supplying a celebrity with drugs that resulted in death. In 2011, Michael Jackson‘s doctor was convicted of involuntary manslaughter for allegedly prescribing the singer a lethal dose of propofol, a powerful anesthetic meant for surgical procedures that he improperly used to treat insomnia. Plus, the two men who supplied rapper Mac Miller with counterfeit oxycodone containing fentanyl leading to his 2018 death were ultimately sentenced to more than 10 years in prison.

Perry had struggled with substance abuse issues since his time on Friends, the hit sitcom in which he starred alongside Jennifer Aniston, David Schwimmer, Courteney Cox, Lisa Kudrow and Matt LeBlanc. The actor previously revealed that he was taking up to 55 Vicodin a day while filming Friends and, at one point, only weighed 128 pounds, per People.

In a resurfaced clip from Aniston’s 2004 interview with Diane Sawyer, the actress broke down in tears over the thought of losing Perry to his addiction.

“He struggled,” Aniston said through tears. “We didn’t know. We, you know, we weren’t equipped to deal with it. Nobody had ever dealt with that. And, you know, the idea of even losing him…”

At the time of his death, the Friends cast released a joint statement before penning their own individual tributes for their late co-star.

“We are all so utterly devastated by the loss of Matthew. We were more than just cast mates. We are a family,” the statement read, per People. “There is so much to say, but right now we’re going to take a moment to grieve and process this unfathomable loss.”

If you or someone you know is struggling with substance abuse, call the SAMHSA National Helpline at 1-800-662-4357.