50 U.S.C. § 23: Jurisdiction of United States courts and judges

After any such proclamation has been made, the several courts of the United States, having criminal jurisdiction, and the several justices and judges of the courts of the United States, are authorized and it shall be their duty, upon complaint against any alien enemy resident and at large within such jurisdiction or district, to the danger of the public peace or safety, and contrary to the tenor or intent of such proclamation, or other regulations which the President may have established, to cause such alien to be duly apprehended and conveyed before such court, judge, or justice; and after a full examination and hearing on such complaint, and sufficient cause appearing, to order such alien to be removed out of the territory of the United States, or to give sureties for his good behavior, or to be otherwise restrained, conformably to the proclamation or regulations established as aforesaid, and to imprison, or otherwise secure such alien, until the order which may be so made shall be performed.