Who Are the Unidentified Federal Police Forces at Portland Protests?

As heavily armed unidentified federal agents dressed in camouflage body armor continue to clash with protesters nightly in Portland, Oregon, many are wondering who exactly they are. The role of these agents is causing an uproar as reports of ‘abduction-style’ detainments of protesters in unmarked vans continue. The agents are from several agencies under the umbrella of Homeland Security. Some wear insignia identifying them as police, but no badges or name are visible.