Chicago's U.S. attorney's office says four members of the city's Milwaukee Kings street gang have been charged with committing murder in aid of racketeering.

Prosecutors say 26-year-old Hector Rojas, 25-year-old Jose Martinez, 21-year-old Santo Lozoya and 22-year-old Pedro Navarro face mandatory life sentences if convicted. The four Chicagoans have pleaded not guilty.

An unsealed grand jury indictment says the Milwaukee Kings engaged in drug trafficking and committed brutal violence to maintain their illegal activities, in part to boost their social-media status. A hearing is set for June 20

The Chicago Crime Commission's Gang Book says the gang was founded in the 1980s along North Milwaukee Avenue. They were linked to the Latin Kings, then allied with the Maniac Latin Disciples. Gang wars forced their move to the North Side.