Johnny Torrio
Frank McErlane (1894–1932) was a Prohibition-era Irish American gangster. He led the Saltis-McErlane Gang, allied with the Johnny Torrio-Al Capone Gang, against rival bootleggers, the Southside O'Donnell Brothers. He is credited with introducing the Thompson submachine gun to Chicago's underworld. The Illinois Crime Survey called him "the most brutal gunman who ever pulled a trigger in Chicago."