Brown says Haim obtained the meds, which included Valium and Soma, through seven different doctors. Brown says investigators have talked to the doctors and they appear to have been duped.
Haim died March 10 after collapsing in his mother's apartment. The Canadian-born star of 1980s films, such as "The Lost Boys" and "License to Drive," struggled with drugs throughout his life. Haim was also suffering from flulike symptoms before his death.
Coroner's officials have said they found four prescriptions in Haim's name in the apartment where he collapsed, and all were prescribed by a doctor treating the actor.
"Corey Haim's death is yet another tragedy linked to the growing problem of prescription drug abuse," Brown said in a written statement published on March 13, after Haim's name was found on a fraudulent prescription that authorities say was obtained through a major drug ring. "This problem is increasingly linked to criminal organizations, like the illegal and massive prescription drug ring under investigation."
Actor Corey Feldman told "The Early Show" the day after Haim's death that he didn't think his friend committed suicide.
"I don't think it was a suicide, and I don't think it was an intentional overdose," he said.
Feldman added that Haim battled addiction his "entire adult life," but that he was pushing forward and caring for his mother, who is battling cancer.
"He made a lot of mistakes. But he always had his talent, he always had his skill and he always tried to be the best person he could."