Kim Richards has been formally charged with one count of petty theft following her shoplifting arrest at Target, the L.A. City Attorney confirms to ET.
The 50-year-old Real Housewives of Beverly Hills star, who completed a stint in rehab in July, pleaded not guilty to the charge on Monday.
ET has learned that before being arrested by Target security officers Sunday night, Richards had filled three carts full of merchandise and then unloaded them one by one into her car. However, Richards was allegedly not charged for one of the carts, totaling in over $600 of toys.
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Van Nuys police officers confirmed the arrest to ET. Since Richards was arrested by Target loss prevention officers, it is a private person's arrest.
Despite reports that Richards was homeless and living out of her car at the time of her arrest, a source tells ET that is not true.
"She rented a home for a few weeks from a friend, and is currently house hunting to find a more permanent residence," says the source. "She is not broke, not living in a car, and not homeless. She only moved out of her old house because she was renting the house, and the house went up for sale."
Richards' ex-husband Monty Brinson insisted to ET that the entire incident must be a mistake.
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"I couldn't imagine Kim stealing or shoplifting anything. She is a giver," he told ET. "I am in complete shock. Guaranteed this must be some kind of mistake, and the facts will come out soon. She was arrested for shoplifting toys in a cart, but this was a clear misunderstanding. This was not alcohol or drug related."
In July, Richards told ET's Nischelle Turner that she "loves sobriety," and learned "a whole lot about myself" during her rehab stay following her arrest for public intoxication at the Beverly Hills Hotel in April.
"I dug deep into my past -- things that happened to me as a child, good and band, teenage years, relationships with all my loved ones, where they need to be mended, where they're very powerful," she said. "I worked on me."
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During the discussion, Richards opened up about the struggle to stay clean after rehab.
"I work every single day at it. Some days are a struggle for sure," she said, emphasizing meditation, and the love, and support, of people around her.
Richards was booked at 7:29 p.m. PT on Sunday at the Valley Jail in Van Nuys, California, and was released Monday afternoon after posting $5,000 bail.
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ET reached out to Target, who is not commenting on Richards' arrest as it is an active investigation.
Watch Richards' discuss sobriety with ET below.