Los Angeles (CNN) -- Two men pleaded not guilty Wednesday to felony charges related to the brutal beating of San Francisco Giants fan Bryan Stow after a Los Angeles Dodgers game in March. Late Wednesday, prosecutors announced they won't charge a woman who's the sister to one defendant and the girlfriend to the other because they don't have enough evidence against her, a spokeswoman said. During their arraignment in Los Angeles County Superior Court, Marvin Norwood, 30, and Louie Sanchez, 29, both of Rialto, California, were ordered by the judge to remain in custody in lieu of $500,000 bail each.
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NEW: A woman who's the sister of one defendant won't be charged, prosecutor's office says
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Victim Bryan Stow, hospitalized since March, remains in serious condition
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Only one witness has identified Louie Sanchez at crime scene, prosecutor says
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No witnesses have identified Marvin Norwood at the crime scene, prosecutor says
Earlier this week, Stow's family reported on their website that @placeholder showed the most response yet since the beating on the Dodgers' home opener: He lifted his left leg slightly when asked and raised his left arm every time family members asked if they could hold his hand.