"JUMPED BY ANTIFA": Independent journalist Nick Sortor recounts the moments before his arrest outside a Portland ICE facility during another night of chaotic protests. | Bill Melugin | Fox News

Experts on antifa, which is shorthand for "anti-fascism," say the movement originates with groups that opposed World War II-era dictators like Italy's Benito Mussolini and Adolf Hitler. Pres. Trump has vowed to designate antifa a terrorist group. But senior Justice Department officials warn against such a move, with one senior official telling Congress it would be "highly problematic." Learn more: https://abcn.ws/2BQpMDr | ABC News