LOS ANGELES (CBS) — Four former Bell city officials, including former City Administrator Robert Rizzo and his former assistant, Angela Spaccia, pleaded not guilty Thursday to corruption charges.

Rizzo, Spaccia, former Mayor Oscar Hernandez and former Councilman Luis Artiga are among eight former city officials accused of misappropriating millions of dollars from the city’s coffers through bloated salaries and loans of taxpayer money.

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The alleged ringleader, Rizzo, is charged with more than 50 counts of fraud, including 44 counts of misappropriation of public funds, six counts of falsification of records by an official custodian, three counts of conflict of interest and one count of public officer crime.

One count was dropped against him Thursday but another was added by prosecutors.

Spaccia, who faced four counts of misappropriation of public funds, was charged with a fourth misappropriation count, plus three counts of conflict of interest.

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The new charges arose from evidence presented during her preliminary hearing, said Jane Robison of the Los Angeles County District Attorney’s Office.

Former Mayor Oscar Hernandez and former Councilman Luis Artiga also pleaded not guilty to corruption-related charges.

A pre-trial hearing was set for May 3.

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