Five arrests have been made amid a federal drug investigation into the death of “Friends” star Matthew Perry.

The Department of Justice said in a press conference Thursday morning that an investigation revealed a “broad underground criminal network,” including Perry’s assistant and doctors, who “took advantage” of the actor by selling him ketamine.

“This network included a live-in assistant, various go-betweens, two medical doctors and a major source of drug supply known as ‘The Ketamine Queen,'” said U.S. Attorney Martin Estrada, announcing the charges. “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 anyways. In the end, these defendants were more interested in profiting off Mr. Perry than caring for his well being.”

The lead defendants in the case are doctor Salvador Plasencia and drug trafficker Jasveen Sangha, Variety reports. Together, they worked with doctor Mark Chavez, Perry’s live-in assistant Kenneth Iwamasa and a “broker” named Erik Fleming to obtain ketamine and sell it to Perry, who died Oct. 28, 2023 at age 54. Chavez, Iwasama and Fleming have pleaded guilty to various charges.

Plasencia and Sangha were both charged with one count of conspiracy to distribute ketamine. Sangha, a North Hollywood resident who holds dual citizenship in the U.S. and U.K., was also charged with several other drug related offenses, NBC reports.

Prior to his death, Perry had reportedly been undergoing ketamine therapy for depression and anxiety. According to the medical examiner’s toxicology report, “At the high levels of ketamine found in his postmortem blood specimens, the main lethal effects would be from both cardiovascular overstimulation and respiratory depression.”