From Wiktionary, the free dictionary
From Malay perampokan. Equivalent to rampok + peng- -an.
perampokan (first-person possessive perampokanku, second-person possessive perampokanmu, third-person possessive perampokannya)
- robbery;
- The act or practice of robbing.
- (law) The offense of taking or attempting to take the property of another by force or threat of force.