The untimely death of "Friends" star Matthew Perry shocked the world. For the public, it was an accidental drowning, but law enforcement seems to be looking into the drug aspect of the case, particularly the involvement of ketamine. This angle is so big that even federal authorities are involved in the investigation.

Law enforcement sources have told TMZ that there is an ongoing investigation regarding where Perry got the ketamine that had a part in the actor's drowning death. The questions law enforcement is asking right now are who provided the drug and under what circumstances.

Several agencies are involved in the investigation, including local Los Angeles police and the DEA. They have already interviewed some key people in Hollywood, though it remains unknown where in the case they are already.

Authorities, both local and federal, have "approached and spoken to people who are known to have a history of drug use or abuse," says the TMZ source, which clarified that these people "are not necessarily the actual source of ketamine, but they could have information leading to the source."

So far, no arrests have been made as to where the ketamine that might have ended up killing Matthew Perry might have come from. A toxicology report following Perry's death has confirmed that he died from acute effects of ketamine.

He passed away while "undergoing ketamine infusion therapy for depression and anxiety more than a week before his death." However, the Los Angeles County Medical Examiner's Office found that the ketamine they found in his system at the time of his death was not from the treatment.

Matthew Perry Had Struggles With Drug Addiction Throughout His Life

When he was still alive, Matthew Perry had a well-documented struggle with drug addiction, which dated back to his time on "Friends," which helped propel him to become one of the biggest TV stars on the planet as Chandler Bing, the ever-sarcastic "Friend" known for his wit.

READ NEXT: Matthew Perry's Death: Matt LeBlanc Shares Touching Tribute for Late 'Friends' Co-Star

According to the Associated Press, the LA medical examiner noted that Perry's last treatment before his death happened over a week and a half before his passing, which meant that the levels of ketamine in his blood found after his death were unexplained as the drug is typically metabolized in a matter of hours.

'Friends' Cast to Celebrate 20th Anniversary of Show's Finale Without Matthew Perry in Bittersweet Moment

The 20th anniversary of when the final episode of "Friends" aired is about to happen. However, this is also the first time that the cast will celebrate it without their Chandler, as this is also the show's first anniversary since Matthew Perry's death.

Aniston, Cox, Kudrow, LeBlanc, and Schwimmer have come together since his death and a source told Us Weekly that they are still trying to figure out how to appropriately mark the 20th anniversary.

"The prospect of having a reunion or a formal get-together without Matthew is bittersweet. There will be a huge void," the source stated. "[But] they know Matthew would've wanted them to carry on and celebrate the show. So that's very much on their minds as they move forward."

READ MORE: Remembering Matthew Perry: Chandler Bing's Sarcastic Quotes From 'Friends'

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Written by: Rick Martin

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