REUTERS/ Annabelle GordonWASHINGTON, United States- President Donald Trump on Saturday authorized the deployment of troops to the northwestern US city of Portland, extending his contentious domestic use of the military to support his mass immigration crackdown. It was not clear if Trump was authorizing the use of troops at ICE facilities nationwide or just in Portland, where protests have been ongoing for months. Protesters in Portland and other cities have intermittently blocked entrances to ICE facilities, prompting some clashes as agents try to clear the area. Federal officials say the gunman, who died from a self-inflicted gunshot, had sought to target ICE agents from a nearby rooftop. Following Kirk's death, Trump announced that he was labeling the diffuse left-wing "Antifa" movement as a "domestic terrorist group."