The suspects face charges that include solicitation of assault and murder, conspiracy and extortion, The Orange County Register reported. The joint federal, state and county investigation, which began in January 2009, was named Operation Stormfront.
Three state indictments were released Thursday at a news conference in Santa Ana, Calif.
"The bottom line is that some very, very, very serious bad guys have been taken off the street for a long time -- if not for life," Sheriff Sandra Hutchens said.
The defendants include a husband and wife -- Wayne Jason Marshall, named in two indictments, and Ruthie Christine Marshall, named in three. Marshall is the only woman in the group.
Investigators said in the course of the investigation another 34 people were charged with parole violations and non-violent crimes. Sixteen more face federal charges that include drug trafficking, fraud and firearms crimes.
Orange County has the largest concentration of white supremacist groups in California, the Anti-Defamation League says.
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