The move was first reported by CNN. Citing unidentified senior administration officials, the news network reported Trump asked White House chief of staff Mick Mulvaney to fire Alles last month. White House officials did not immediately confirm the report.
The decision was "part of a larger shuffle at the Department of Homeland Security," according to Fox News. The network reported Alles will continue to serve as director of the Secret Service until his replacement takes over.
News of Alles’ planned exit came one day after reports indicated Nielsen resigned under pressure from the president, who has been frustrated over issues at the southern border.
Alles, who in 2011 retired from the U.S. Marine Corps. as a two-star general, took over as head of the Secret Service in April 2017, The New York Times reported. Before taking the role, Alles served as acting deputy commissioner of U.S. Customs and Border Protection.