A police cordon refers to an area that is cordoned off with barriers or tape by the police to prevent people from entering or leaving. It is done for safety or investigation purposes during emergencies or crime scenes. Full definition
Virginia State Police cordon off an area around the site where a car ran into. (petesgrillandpizza.com)
Riot police cordon off areas at Singapore's Race Course Road on Sunday to maintain order following a riot Sunday in the Little India neighborhood. (npr.org)