Five people including his personal assistant and two doctors have been charged in connection with death in what prosecutors called a 鈥渂road underground criminal network鈥� dedicated to getting the 鈥淔riends鈥� star the powerful surgical anesthetic that killed him.

The doctors preyed on Perry鈥檚 history of addiction in the final months of his life last year to provide him with ketamine in amounts they knew were dangerous, U.S. Attorney Martin Estrada said as he .

鈥淭hey knew what they were doing was wrong,鈥� Estrada said. 鈥淭hey knew what they were doing was risking great danger to Mr. Perry. But they did it anyway.鈥�

One doctor even wrote in a text message, 鈥淚 wonder how much this moron will pay鈥� and 鈥淟ets find out,鈥� according to an indictment unsealed Thursday.

Perry died in October due to a ketamine overdose and prosecutors said he received several injections on the day he died from his live-in personal assistant, Kenneth Iwamasa, who found Perry dead later that day and was the first to talk to investigators.

Ketamine has seen a huge surge in use in recent years as a treatment for depression, anxiety and pain. While the drug isn鈥檛 approved for those conditions, doctors are free to prescribe drugs for so-called off-label uses.

Perry had been receiving regular ketamine infusion treatments for depression 鈥� in amounts not nearly enough to account for his death 鈥� from his regular doctors, who were not among those charged, authorities said.

When those doctors refused to give him more, he went in desperation to others.

鈥淲e are not talking about legitimate ketamine treatment,鈥� Estrada said. 鈥淲e鈥檙e talking about two doctors who abused the trust they had, abused their licenses to put another person鈥檚 life at risk.鈥�

DEA Administrator Anne Milgram said in one instance the actor paid $2,000 for a vial of ketamine that cost one of the physicians about $12. Perry paid the doctors about $55,000 in cash in the two months before his death, Estrada said.

Two of the people, including one of the doctors charged, were arrested Thursday, Estrada said. Two of the defendants, including Iwamasa, have pleaded guilty to charges already, and a third person has agreed to plead guilty.

Multiple messages left seeking comment from lawyers or offices for all the defendants have not yet been returned.

Among those arrested Thursday are Dr. Salvador Plasencia, who is charged with seven counts of distribution of ketamine and also two charges related to allegations he falsified records after Perry鈥檚 death.

The other person arrested Thursday is Jasveen Sangha, who prosecutors described as a drug dealer known to customers as the 鈥渒etamine queen.鈥� Ketamine supplied by Sangha caused Perry鈥檚 death, authorities said.

Sangha and Plasencia could make their first court appearances later Thursday. Plascencia could get up to 120 years in prison if convicted, prosecutors said, and Sangha could get life in prison.

Records show Plascencia鈥檚 medical license has been in good standing with no records of complaints, though it is set to expire in October.

A San Diego physician, Dr. Mark Chavez, has agreed to plead guilty to conspiracy to distribute ketamine. Prosecutors allege Chavez funneled ketamine to Plasencia, securing some of the drug from a wholesale distributor through a fraudulent prescription.

The prosecutor said the defendants exchanged messages soon after Perry鈥檚 death referencing ketamine as the cause of death. Estrada said they deleted messages and falsified medical records in an attempt to cover up their involvement.

that they were working with the U.S. Drug Enforcement Administration and the U.S. Postal Inspection Service with a probe into why the 54-year-old had so much of the surgical anesthetic in his system.

Iwamasa found the actor face down in his hot tub on Oct. 28, and paramedics who were called immediately declared him dead.

The assistant received the ketamine from Erik Fleming, who has pleaded guilty to obtaining the drug from Sangha and delivering them to Iwamasa. In all, he delivered 50 vials of ketamine for Perry鈥檚 use, including 25 handed over four days before the actor鈥檚 death.

that the amount of ketamine in his blood was in the range used for general anesthesia during surgery.

But it had been 1 1/2 weeks since his previous legitimate treatment, the medical examiner said, and the drug is typically metabolized in a matter of hours.

Estrada said that Plasencia had witnessed Perry freeze up and saw his blood pressure spike after injecting him with the drug, but still left several vials with Iwamura for the actor to inject later.

The medical examiner listed ketamine as the primary cause of death, which was ruled an accident with no foul play suspected, the report said. Drowning and other medical issues were contributing factors, the coroner said.

Perry had years of dating back to his time on 鈥淔riends,鈥� when he became one of the biggest television stars of his generation as Chandler Bing alongside Jennifer Aniston, Courteney Cox, Lisa Kudrow, Matt LeBlanc and David Schwimmer for 10 seasons from 1994 to 2004 on .

Drug-related celebrity deaths have in other cases led authorities to prosecute the people who supplied them.

After rapper of cocaine, alcohol and two of the men who provided him the fentanyl were . One was sentenced to more than 17 years in federal prison, the other to 10 years.

And after died in 2009 from a lethal dose of propofol, a drug intended for use only during surgery and other medical procedures, not for the insomnia the singer sought it for, his doctor, , was convicted of involuntary manslaughter in 2011. Murray has maintained his innocence.