MINNEAPOLIS (AP) — Federal agents launched a sweeping undercover surveillance operation earlier this year targeting progressive organizations, labor unions and other groups protesting the immigration crackdown then raging through Minneapolis, according to court documents filed Thursday.

The program, dubbed Operation Puppet Master, was aimed at what officials called a network of conspirators helping “violent opportunists and agitators.” The documents were filed in a case involving 15 people charged by federal prosecutors in June with impeding the crackdown, accusing them of conspiring against the federal government through a range of actions, from throwing ice chunks to setting up blockades.