Trump: 'Going to Find Out' How to Track Antifa

President Donald Trump admitted that designating antifa as a domestic terror organization will be difficult for law enforcement to track, but he vowed the FBI and Justice Department will find a way.

"We're going to find out," Trump told an NPR reporter in the press gaggle aboard Air Force One on the trip back from the U.K. this week.

"Did they have anything to do with your network — antifa?" Trump asked the NPR reporter, apparently in jest when she told Trump which outlet she was with.

Trump on Wednesday announced he was designating the anti-fascist movement antifa a "major terrorist organization," a move that follows last week's fatal shooting of conservative leader Charlie Kirk.

Trump posted the declaration on Truth Social while on a state visit to the United Kingdom, hours after attending a state banquet at Windsor Castle.

"I am pleased to inform our many U.S.A. Patriots that I am designating ANTIFA, A SICK, DANGEROUS, RADICAL LEFT DISASTER, AS A MAJOR TERRORIST ORGANIZATION,” Trump wrote, adding that he would "strongly recommend that those funding ANTIFA be thoroughly investigated in accordance with the highest legal standards and practices."

Vice President JD Vance began this week sitting in as guest host for "The Charlie Kirk Show" podcast, vowing the U.S. government will "go after the NGO" [nongovernmental organizations] networks like antifa.

"There's a lot of questions about the investigation, where we are in the investigation," Vance said. "I want to be respectful to the FBI process, but just know that we are on top of this, and the entire administration is trying to do as much as possible to find everything that we can about what led to this.

"We are going to go after the NGO [nongovernmental organizations] network that is promoting violence in this country," he added. "We have to talk about this incredibly destructive movement of left-wing extremism that has grown up over the last few years and is part of the reason I believe Charlie was killed by an assassin's bullet."

White House deputy chief of staff Stephen Miller blamed a "vast domestic terror movement" for Kirk's assassination, adding the White House will use Justice Department and Department of Homeland Security resources to "identify, disrupt, dismantle, and destroy" domestic terrorist networks in America.

"The [organized] doxing campaign, the organized riots, the organized street violence, the organized campaigns of dehumanization vilification, posting people's addresses, [and] combining that with messaging that's designed to trigger inside violence and the actual organized cells that carry out and solicit the violence," he added. "It is a vast domestic terror movement.

"And with God as my witness, we are going to use every resource we have at the Department of Justice, Homeland Security and throughout this government to identity, disrupt, dismantle, and destroy these networks and make America safe again. It will happen, and we'll do it in Charlie's name."