drag·net 
/ˈdrægˌnɛt/ noun
plural drag·nets /ˈdrægˌnɛt/ noun [count] 1 : a series of actions that are done by the police in order to catch criminals
▪ Nine suspects were caught in the police dragnet. 2 : a net that is pulled along the bottom of a river, lake, pond, etc., to search for or collect something
▪ Nine suspects were caught in the police dragnet.
