An obscure colloquism referring to the Police (Fuzz,Pig,Copper,etc.).

Origin is unknown, but apparently gives reference to "Hawaii 5-0" (a popular television show of the late 1970s), together with the inherent ape-like qualities associated to low-ranking law enforcers.
"...Quick, turn down the music - Monkey Five-Oh is right outside!"
by DardaDos August 7, 2005
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