Ronald Vitiello appointed chief of U.S. Border Patrol

A Border Patrol vehicle is seen guarding at a newly built section of the U.S.-Mexico border fence at Sunland Park, U.S. opposite the Mexican border city of Ciudad Juarez, Mexico January 26, 2017. REUTERS/Jose Luis Gonzalez

WASHINGTON (Reuters) - Ronald Vitiello has been appointed chief of the U.S. Border Patrol, according to an internal memo seen by Reuters on Tuesday, replacing Mark Morgan, who had been asked to step down as the agency moves toward tougher immigration enforcement under the Trump administration. Vitiello's appointment was announced in a memo by Kevin McAleenan, acting commissioner of the U.S. Customs and Border Protection, which oversees the Border Patrol. (Reporting by Julia Edwards; Writing by Eric Beech)