New criminal investigation has been launched into the death of Friends star Matthew Perry

Seven months following the tragic passing of Friends star Matthew Perry, a joint criminal investigation into his death has been announced by police.

The 54-year-old was found deceased at his home in Los Angeles on 28 October last year

His family wrote in a statement at the time: "We are heartbroken by the tragic loss of our beloved son and brother.

"Matthew brought so much joy to the world, both as an actor and a friend. You all meant so much to him and we appreciate the tremendous outpouring of love."

A post-mortem examination concluded that Perry died from the 'acute effects of ketamine', while also listing contributing factors that included 'drowning, coronary artery disease and the effects of buprenorphine'.

His death was also ruled as being accidental.

This week, however, Los Angeles Police Department have confirmed that a joint police investigation into the circumstances of the star's death has commenced.

Speaking to PA, officers from LAPD revealed they'll be continuing to collaborate with the Drug Enforcement Administration on the 'open investigation', following the medical examiner's initial assertions.

Matthew Perry passed away last year (David M. Benett/Dave Benett/Getty Images)

According to reports, the investigation will enquire into how Perry obtained the general anaesthetic.

As per The Guardian, the actor - who'd been open about his substance abuse throughout his career - was receiving 'ketamine infusion therapy for depression and anxiety', something which Perry had spoken about in his 2022 memoir, Friends, Lovers and The Big Terrible Thing.

According to reports, Perry's last known treatment one and a half weeks before his death, with the ruling determining that the drugs in his system 'could not be from that infusion therapy', but was unable to specify the 'exact method of intake'.

The autopsy also says that ketamine's lifespan is 'three to four hours or less', as per The Hollywood Reporter.

It is unclear how long the investigation - which was first reported by TMZ - has been going on for, and no arrests have also been made in regards to the probe.

Tyla has contacted LAPD and the DEA for further comment.

Following his death, millions of Friends fans - as well as Matthew's five co-stars, Jennifer Aniston, Courtney Cox, Lisa Kudrow, Matt Le Blanc and David Schwimmer - have since honoured the comedy star's life with a series of tributes.

The circumstances surrounding the actor's death are still being investigated. (Michael Buckner/Getty Images)

Kudrow thanked the late star for 'all I learned about GRACE and LOVE through knowing you' in an emotional Instagram statement.

Schwimmer (Ross Geller) said of his castmate: "You had heart. Which you were generous with, and shared with us, so we could create a family out of six strangers."

Anniston (Rachel Green) described her beloved friend as her 'little brother', whilst Matt Le Blanc (Joey Tribbiani) said their time on the show side-by-side was 'among the favourite times' in his life.

And Cox - who played Perry's on-screen wife Monica Geller - shared several snaps of their time together on Instagram, writing: "I am so grateful for every moment I had with you Matty and I miss you every day."