National Guard troops called on to active-duty by President Donald Trump arrived at the footsteps of the Washington Monument on Tuesday as part of his plan to address what he insists is "out of control" crime in the nation's capital. Col. Dave Butler, an Army spokesperson, said the troops were called on to help local law enforcement with logistics support, transportation and administration duties, as well as being visible around the National Mall. "That's part of our assignment – to go to the national monuments and be present," he told ABC News. MORE: Trump puts DC police department under federal control, deploys National Guard The deployment of troops on U.S. soil is legal to an extent, with the president holding the power to wrangle service members in times of extraordinary crisis. But their duties are also limited to protecting federal personnel and federal property unless the president declares an insurrection, which he has not done. It was not immediately clear why the presence of U.S. troops along the National Mall was needed, other than to put Trump's orders on display. The area, marked by museums, monuments and long stretches of grass, is known as a relatively safe part of the city that attracts mostly tourists and school groups. The troops are expected to have access to weapons but will not carry them, Butler said. MORE: Hours after Trump seized DC police force, a man was gunned down in Logan Circle Trump has railed against what he calls rampant crime in D.C. On Monday, he called a press conference to announce he would take over the Washington, D.C., police department and activate troops from the D.C. National Guard. Officials said 100 Guard troops reported to duty on Tuesday with more expected throughout the week. "Something's out of control," Trump said Monday of D.C. crime. "But we're going to put it in control very quickly, like we did in the southern border. I'm announcing a historic action to rescue our nation's capital from crime, bloodshed, bedlam and squalor and worse. This is Liberation Day in D.C., and we're going to take our capital back." Trump's control of the D.C. police force expires in 30 days, after which Congress would have to weigh in. Earlier on Tuesday, an Army spokesperson said the Guard troops had not been given a mission yet other than to support law enforcement. The expectation was that the service would need the rest of the week to account for the 800 troops and mobilize them before deploying them next week.