The Los Angeles Police Department is collaborating with the Drug Enforcement Administration (DEA) to find the origin of the ketamine responsible for Matthew Perry's demise last year, according to law enforcement officials.

The renowned actor, known for his role as Chandler Bing in "Friends," passed away at 54 on October 28, 2023. A postmortem examination, disclosed by PEOPLE in December, attributed his death to acute ketamine effects.  

Jennifer Aniston and Matthew Perry
(Photo: Getty Images/Jon Koplaff)

The autopsy report also cited additional factors such as drowning, coronary artery disease, and the effects of buprenorphine, a medication utilized in treating opioid addiction. 

RELATED: Jennifer Aniston Details Last Day Of Matthew Perry Alive: 'He Was Happy'  

His death was officially deemed accidental. By December, the Los Angeles County Medical Examiner-Coroner had concluded its inquiry, PEOPLE reported. Subsequent to the release of the medical examiner's findings, the LAPD initiated an inquiry into the circumstances surrounding his fatal drug overdose in December.

Matthew Perry
(Photo: Jason Merritt/Getty Images)

TMZ broke the news about the investigation into the origin of the ketamine. 

While authorities have interviewed multiple individuals, no arrests have been executed. 

RELATED: 'Friends' Streaming Surged Day After Matthew Perry's Death, Becomes 7th Most Streamed Show 

Matthew Perry
(Photo: Getty Images/Angela Weiss)

When reached for comment on Tuesday, the DEA reportedly opted not to respond and referred inquiries to the LAPD for updates. 

The autopsy revealed that Perry was undergoing ketamine infusion therapy at the time of his death. In his memoir, "Friends, Lovers, and the Big Terrible Thing," published in 2022, he candidly discussed his battles with addiction. 

"I wanted to share when I was safe from going into the dark side again," he told PEOPLE in 2022. "I had to wait until I was pretty safely sober and away from the active disease of alcoholism and addiction to write it all down. I was pretty certain that it would help people if I did."