Roundup (police action)

Round up of Jews by the Nazi occupiers in Amsterdam in February 1941.

A roundup is a police / military operation of interpellation and arrest of people taken at random from a public place, or targeting a particular population by ethnicity, appearance, or other perceived membership in a targeted group. To ensure operational success, organizers rely on the element of surprise in order to reduce the risk of evasion as much as possible. When the operation involves large numbers of individuals not targeted for any perceived group membership, it may be called a mass arrest.