Anna Nicole Smith's longtime partner and attorney, Howard K. Stern, and a doctor were jailed Thursday on charges of conspiring to furnish drugs before her death in 2007, authorities said.

Another doctor facing charges was expected to turn herself in Monday, authorities said.

The doctors and Stern devised a plan to use fake names so that Smith could be prescribed "thousands of pills," California Attorney General Jerry Brown said.

"She was obviously addicted," Brown said. "These doctors had a medical obligation to prescribe medicine in a professional way. Evidence will show this did not happen."

The former Playboy playmate and reality TV star died from an accidental overdose of prescription drugs. At the time of her death, several prescription medications -- both in Smith's and Stern's names -- were found in the room.

Officials said prescription and over-the-counter drugs were found in Smith's system, including three antidepressants or anti-anxiety drugs. Also found in toxicology testing was human growth hormone and chloral hydrate, a sleep medication, officials said.

Stern, 40, and doctors Sandeep Kapoor, 40, and Khristine Eroshevich, 61, were each charged with eight felonies, including conspiring to furnish controlled substances, unlawfully prescribing a controlled substance and obtaining fraudulent prescriptions from June 2004 to January 2007 -- only weeks before the playmate's death.

Kapoor and Eroshevich were each also charged with obtaining a prescription for opiates by "fraud, deceit or misrepresentation." Each was also charged with one count of obtaining a prescription for opiates by giving a false name or address, according to the Los Angeles District Attorney's Office.

Stern and Kapoor were arrested Thursday, Brown said. They were being held in lieu of a $20,000 bail. Stern turned himself in at a Los Angeles County jail, posted bail and was released, a police spokesman said. Eroshevich was to turn herself in Monday, Brown said.