President Donald Trump has implemented sweeping uses of executive authority since returning to office in January. As he continues his crackdown on unauthorized immigration, the president is now reportedly looking to use a little-known law from the early days on the United States,

Experts predict a swift legal challenge to Trump's 'novel' approach of invoking wartime powers to target immigration.

The act is a wartime authority that allows the president to detain and deport non-U.S. citizens from enemy countries.

Trump is expected to invoke the Alien Enemies Act as part of the efforts to carry out mass deportations, according to two U.S. officials familiar with the matter.

President Donald Trump is expected to invoke the Alien Enemies Act, a wartime law granting the president authority to detain or deport nationals of an enemy country, two U.S. officials familiar with the matter told ABC News.