LOS ANGELES -- Forty alleged members of the Aryan Brotherhood, a white supremacist prison-based gang, have been indicted on racketeering charges stemming from a series of violent crimes that included 16 murders, officials said Thursday.

Thirty defendants are in prisons around the country for other offenses. Eight other defendants were arrested Thursday in California, Florida, and Louisiana while two remain at large, said Thom Mrozek, a spokesman for the U.S. Attorney's office.

The 10-count indictment was handed down Aug. 28 and unsealed Thursday. The indictment alleges that members of the Aryan Brotherhood killed or attempted to kill people to control drug trafficking, gambling and extortion in the federal and California state prison systems, Mrozek said.

Some of the indictments involved murders of black inmates as part of what officials called "an Aryan Brotherhood race war."

The gang's alleged activities outside of prisons, including drug dealing, were part of the reason it was targeted, Mrozek said.

"We saw them attempting and in some ways achieving an expansion of their power outside of prison walls," he said.

Non-inmates arrested included four California women accused of relaying information for the gang and a California man accused of distributing the gang's drug profits.

The gang, which was founded by white inmates in 1964, has a reputation for assaulting or killing anyone considered a threat to the organization, including those who acted as informants for law enforcement, Mrozek said.

In addition to the arrests, officials executed 80 search warrants at residences, offices and prison cells in California, Louisiana, Illinois, Pennsylvania, Georgia, Colorado, Massachusetts, Florida, Washington, Nebraska, Connecticut and New York.