A shootout is a gun battle between armed groups. A shootout often, but not necessarily, pits law enforcement against criminal elements; it could also involve two groups outside of law enforcement, such as rival gangs. A shootout in a military context (i.e. regularly constituted armed forces or even guerrilla or insurgent forces) would usually be considered a battle or firefight (depending on size), rather than a shootout. Shootouts are often portrayed in action films and western films.
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... children, senior citizens and a woman with disibility, the shootout began when the on-board TV broadcasted the arrest of his younger brother ...