From Wikipedia entry [Kettling](https://en.m.wikipedia.org/wiki/Kettling): > Kettling (also known as containment or corralling) is a police tactic for controlling large crowds during demonstrations or protests. It involves the formation of large cordons of police officers who then move to contain a crowd within a limited area. Protesters either leave through an exit controlled by the police, leave through an uncontrolled gap in the cordons, or are contained, prevented from leaving, and arrested. ## Resources [How to win at kettling - The Anarchist Library](https://theanarchistlibrary.org/library/anarch-ish-how-to-win-at-kettling-a-guide-for-non-policemen): A guide for non-policemen