Matthew Perry's assistant 'repeatedly' injected Friends star with ketamine on the day he died

Kenneth Iwamasa "repeatedly" injected Matthew Perry with ketamine despite having no medical training , it has emerged.

Iwamasa, who was the actor's live-in assistant, was one of five defendants charged in relation to Matthew's death . Iwamasa has pleaded guilty to one count of conspiracy to distribute ketamine causing death, the Department of Justice announced in a press conference.

The DoJ said Matthew's assistant injected him with ketamine "repeatedly", including on the day of the actor's death.

• Matthew Perry drug dealers mocked him with cruel 'moron' texts before his dead as arrests made

• Jennifer Aniston 'figuring out' how to mark Friends milestone after Matthew Perry's death

Federal criminal charges are also being pressed against two medical doctors Salvador Plasencia and Mark Chavez, as well as "various go-betweens" including Erik Flemming and Jasveen Sangha.

During a press conference on Thursday, United States Attorney Martin Estrada said that since the investigation started after Perry's death in October, "a broad underground criminal network responsible for distributing large quantities of ketamine" was revealed. He added: "These defendants took advantage of Mr. Perry's addiction issues to enrich themselves."

"They knew what they were doing was wrong. They knew what they were doing was risking great danger to Mr. Perry but they did it anyway," Estrada continued.

Sangha is up against a slew of charges including conspiracy to distribute ketamine, methamphetamine possession, and running a drug-involved premises. It's been reported that Sangha dealt "large amounts" of ketamine to Matthew, with officials stating in a press briefing that she flogged 50 vials of the drug to him for a cool $11,000.

• Jimmy Fallon faces furious backlash as TV viewers have only one thing to say following toe-curling stunt

Dr Plascencia is also facing the music with charges for conspiring to distribute the same drug. Iwamasa has copped to a guilty plea for a distribution-related conspiracy charge that ended in death.

In the same vein, Dr Chavez has owned up to his part in the ketamine distribution conspiracy. Fleming has acknowledged guilt for one count of conspiracy to distribute ketamine, plus another count for distributing the substance resulting in death.

Fleming and Iwamasa might be staring down the barrel of a 15 to 25-year stretch in the clink, while Chavez could be looking at a maximum of 10 years in the slammer. Sangha is potentially on the hook for life in prison, and Plasencia could be slapped with up to 120 years in federal lock-up.

For all the latest news straight to your inbox, sign up for our FREE newsletters here .