(Adds background about case)
By Laila Kearney
SAN FRANCISCO, April 8 (Reuters) - A prominent Democratic California state senator and gun-control advocate pleaded not guilty in a federal courtroom in San Francisco on Tuesday to charges of corruption and conspiracy to traffic in firearms.
Leland Yee, 65, who was arrested last month and has since been suspended with pay, was criminally charged along with two dozen other individuals in a broad sweep of suspected organized crime and corruption activity in San Francisco.
He is the third California state senator to face criminal charges this year in separate cases that have cost Democrats a cherished two-thirds majority in an election year.
A 31-page indictment returned by a grand jury last week accuses Yee, a one-time candidate for mayor of San Francisco, of accepting cash from an undercover FBI agent posing as a customer seeking to purchase illegal weapons.
The indictment also says Yee and his campaign consultant, Keith Jackson, sought to enrich themselves and pay off debt from Yee's failed mayoral campaign by accepting bribes.
Among others indicted with Yee was Raymond "Shrimp Boy" Chow, an accused Chinatown underworld figure charged with money laundering and conspiracy. (Reporting by Laila Kearney; Writing by Steve Gorman; Editing by Cynthia Johnston and Gunna Dickson)