Eight years after this film's release, Fred Williamson produced, directed, and wrote Les 4 justiciers (1982), which reunited him with Jim Brown and Jim Kelly. Williamson conceived the idea to do another sequel during a break between filming Chicago Cop (1983) and Vigilante (1982). The funding for the film, crew, scouting locations, and actors all came together quickly, and the movie was shot in about a month. Williamson considers that film a true sequel to this one.
The movie was originally supposed to star Jim Brown, Richard Roundtree, and Ron O'Neal. Roundtree had to pull out due to doing the "Shaft" TV series at the time and O'Neal no longer wanted to do blaxploitation roles.
The films' stars Fred Williamson, Jim Brown, and Jim Kelly would all go on to star together in La chevauchée terrible (1975), which was released by Twentieth Century-Fox a year after this film. In a way, it was sequel to this film, only in a Western setting.
Fred Williamson and Jim Brown are former NFL players, and Jim Kelly was a black belt professional martial artist.
A sequel to the film was proposed by star Fred Williamson which would've featured the return of him, Jim Brown and Jim Kelly in another adventure after the success of this film. Unfortunately, Warner Bros. and Allied Artists were not really interested in a sequel and the idea was scrapped.