(NewsNation) — Authorities announced they have charged five people who ran what they described as an underground ketamine ring in connection with the death of “Friends” star Matthew Perry.

The defendants are Jasveen Sangha, 41, also known as “The Ketamine Queen,” Dr. Salvador Plasencia, 42, Dr. Mark Chavez, 54, Eric Fleming, 54, and Kenneth Iwamasa, 59.

Two of the people arrested pleaded not guilty Thursday afternoon and only one was granted release.

Perry was found dead in a hot tub at his California home in October of 2023. An autopsy report concluded his death was due to the acute effects of ketamine. While Perry had previously undergone ketamine treatment for depression, the medical examiner concluded that the drugs in his system were from recreational use based on the timing of his last treatment session.

Here’s what we know about those charged in Perry’s death:

Jasveen Sangha

Sangha, also known as the “Ketamine Queen,” operated a stash house and distributed ketamine and other illegal drugs, prosecutors said.

U.S. Attorney Martin Estrada said in a press conference that Sangha knew ketamine was dealing and was connected to the death of Cody McLaury, who also died from ketamine she distributed.

Sangha is being charged with one count of conspiracy to distribute ketamine, one count of maintaining a drug-involved premises, one count of possession with intent to distribute methamphetamine, one count of possession with intent to distribute ketamine and five counts of distributing ketamine.

Dr. Salvador Plasencia

A physician, Plasencia had previously applied for a license from the Drug Enforcement Administration to dispense and prescribe controlled substances for legitimate medical purposes.

Court documents say Plasencia acted outside the scope of professional practice to distribute ketamine and also taught Iwamasa how to inject the drug.

Plasencia is facing one count of conspiracy to distribute ketamine, seven counts of distribution of ketamine and two counts of altering and falsifying documents or records related to the federal investigation.

Kenneth Iwamasa

Iwamasa was the live-in personal assistant for Perry and the person who found Perry in the hot tub. Iwamasa had no medical training.

Investigators said Iwamasa was the one who injected Perry with ketamine on multiple occasions despite his lack of training.

Iwamasa pleaded guilty to one count of conspiracy to distribute ketamine causing death and admitted to repeatedly injecting Perry including multiple injections on the day Perry died.

Dr. Mark Chavez

Chavez, like Plasencia, had also applied for a DEA license to prescribe controlled substances for medical use.

Chavez, like Sangha, is accused of obtaining ketamine that Iwamasa, Plasencia and Fleming would distribute. He also had former connections to a legitimate ketamine clinic.

Chavez pleaded guilty to one count of conspiracy to distribute ketamine. In his plea agreement, he admitted to diverting the drug from his former clinic, making false representations to a wholesale ketamine dealer and submitting a fraudulent prescription in the name of a former patient.

Eric Fleming

Fleming was described by investigators as an acquaintance of Perry’s. He allegedly helped obtain ketamine and distributed it to Perry, including giving Iwamasa 50 vials of ketamine, half of which were delivered four days before Perry’s death.

He pleaded guilty to one count of conspiracy to distribute ketamine and one count of distribution of ketamine resulting in death.