Los Angeles, California (CNN) -- Corey Haim's death is linked to an "illegal and massive prescription-drug ring," California Attorney General Jerry Brown said Friday.
Brown's office is investigating "an unauthorized prescription under the former child star's name that was found during an ongoing investigation of fraudulent prescription-drug pads ordered from a vendor in San Diego."
"These prescriptions are very recent, and it involves Oxycontin and we're not talking just 40 pills, more than that," Brown said in an interview Friday with CNN Radio.
The announcement comes before the coroner has ruled on what killed Haim, the 1980s teen movie actor who struggled for decades with drug addiction.
Haim, 38, died early Wednesday after collapsing in the Los Angeles apartment he shared with his mother, authorities said.
"Corey Haim's death is yet another tragedy linked to the growing problem of prescription-drug abuse," Brown said. "This problem is increasingly linked to criminal organizations, like the illegal and massive prescription-drug ring under investigation."
Brown said the ring uses stolen doctor's identities to order prescription-drug pads that are used to write counterfeit prescriptions.
"The doctor whose name is printed on the form is usually unaware that his or her identity has been stolen for this purpose," Brown said.
Haim got two powerful drugs from a pharmacy 11 days before his death, according to a source with knowledge of the transaction.
His primary-care doctor did not know about the prescriptions and called the pharmacy two days later to find out what Haim had been given, the source said.
Brown's announcement did not specify whether any of the prescription drugs found in Haim's apartment after his death were illegally obtained.
Several prescription-drug bottles were taken from Haim's apartment, Los Angeles County Deputy Coroner Ed Winter said Friday.
Although the bottles indicated the drugs included Vicodin, Valium and Soma, no tests have been done to confirm what they are, he said.
Haim had a prescription for the muscle relaxer Soma and the narcotic pain reliever Norco filled at a pharmacy on February 26, a source with knowledge of the transaction said.
Two days after Haim personally picked up the drugs, his primary-care doctor called the San Fernando Valley pharmacy to ask about the prescriptions, the source said.
The doctor said that "Haim was not feeling well" and he needed to know what drugs had been prescribed for the actor, the source said.
The source, who worked at the pharmacy, asked not to be identified because his employer had not authorized him to talk.
Haim's manager, Mark Heaslip, and close friend Corey Feldman both said Haim began seeing an addiction specialist two weeks before his death.
Tiffany Shepis, who was engaged to be married to Haim last May, said on HLN's "Issues With Jane Velez-Mitchell" that he was taking large amounts of Valium and Vicodin during their yearlong relationship.
"You're talking about a person that, at the time when I knew him, you know, was ingesting 40 some-odd pills a day," Shepis said.
Although the autopsy showed Haim's heart was enlarged and he had fluid in his lungs, the coroner's chief investigator said a drug overdose has not been ruled out as the cause of the actor's death.
"You can have somebody with an enlarged heart and some other medical conditions, but you don't know if the actual cause of death is from illegal substances, medication or heart failure," Los Angeles County Deputy Coroner Ed Winter said Friday.
Heaslip said the enlarged heart was evidence that Haim's death was not caused by a drug overdose, but Winter disputed that.
"There were some preliminary findings and we agreed to let the mother know what those were," Winter said. "It was explained to her that even though this is some preliminary findings that the doctor observed, there wouldn't be a final cause of death until the final toxicology tests are back."
The cause of death may not be determined for another six weeks, Winter said.
Feldman, a longtime friend and frequent co-star, asked Wednesday that people not "jump the gun" to conclude a drug overdose killed Haim.
Heaslip, manager to both Feldman and Haim, said Haim had seemed to be winning his battle against drug abuse in the weeks before his death.
Haim was "weaned down to literally zero medications" by an addiction specialist in the two weeks before his death, Heaslip said.
The doctor "put him on a new line of medications," Feldman said on CNN's "Larry King Live" Wednesday.
Haim's death came as his career was picking up, with Haim booking "movie after movie," Heaslip said. His latest film is set for release soon, he said.
Haim's most famous role was in the 1987 movie "The Lost Boys," in which he appeared with Feldman. Haim played the role of a fresh-faced teenager whose brother becomes a vampire.
In later years, the two friends, who appeared in eight movies together, struggled with drug abuse and went their separate ways. They reunited for a reality show, "The Two Coreys," in 2007, but A&E Network canceled the program after slightly more than a year.
In a 2007 interview on CNN's "Larry King Live," Haim and Feldman discussed their battles with drugs. Feldman told King that he had gotten clean, but it took Haim longer.
Haim called himself "a chronic relapser for the rest of my life."
"I think I have an addiction to pretty much everything," he said. "I mean, I have to be very careful with myself as far as that goes, which is why I have a support group around me consistently."
Haim was born December 23, 1971, in Toronto, Ontario, according to a biography on his Web site. He made his first television appearance in 1982 on the Canadian series "The Edison Twins." His first film role was in the 1984 American movie "First Born."
Haim also won rave reviews for his title role in the 1986 film "Lucas." Film critic Roger Ebert said of him at the time, "If he continues to act this well, he will never become a half-forgotten child star, but will continue to grow into an important actor."
After "The Lost Boys," Haim and Feldman appeared in "License to Drive" and "Dream a Little Dream."
CNN's Brittany Kaplan and Jack Hannah contributed to this report.