The Purge movie and TV series celebrate an annual national holiday known as the Purge, in which all crimes, including murder, are legal for a 12-hour period. Undercover agents are hired to incite and manipulate the poor to kill each other. At the commencement of the 12-hour national holiday, a broadcast notice/alarm is played.
People are blasting this commencement notice in the streets during the riots, and freaking some people out.
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