Matthew Perry's Death Is Under Investigation

Investigators have been seeking to learn more about the ketamine in Perry's system at the time of his death.

Months after he died, Friends star Matthew Perry's death is under investigation. On Saturday, Oct. 28, first responders discovered Perry's body after receiving a call to his residence. The actor's death was later ruled accidental and revealed to be caused by acute effects of ketamine in an autopsy report obtained by PEOPLE

Now, TMZ reports that police sources have stated there is an ongoing investigation into where Perry got the ketamine that was found in his system when he died. More specifically, they want to know who gave him the drug, and what were the circumstances of the situation.

According to sources who spoke with TMZ, local law enforcement and DEA officials have spent months investigating these aspects of Perry's death, though at this time it is unclear where things stand. TMZ reports that "some key people in Hollywood" have been interviewed, though no names were provided to them.

It's claimed that the individuals who have been spoken to are people who have substance abuse issues in their background. At this time, no arrests have been made.

In addition to their ketamine determination, the coroner's office also noted some contributing factors in Perry's death, such as drowning, coronary artery disease and buprenorphine effects (a medication used to treat opioid use disorder).

Perry had been open in the past about his struggles with substance abuse and had even helped peers — such as Friends co-star Hank Azaria — to get sober.

If you or someone you know is struggling with substance abuse or addiction, please call the National Drug Helpline at (844) 289-0879.