Transcript for Homeland Security purge continues with removal of Secret Service chief
the major headline unfolding in Washington. President trump firing the head of the secret service after forcing out homeland security secretary kirstjen Nielsen. What's behind all this? ABC's senior national correspondent Terry Moran tonight at the white house. Reporter: President trump is cleaning house at homeland security. First, forcing out secretary kirstjen Nielsen, the public face and prime defender of the family separation approach the administration said would deter migrants. Today, outside of her home, Nielsen ever the team player. I just want to thank the president again for the tremendous opportunity to serve this country. I share the president's goal of securing the border. Reporter: Nielsen's ouster comes just two days after trump dumped his own nominee to head I.C.E., Ron Vitiello. Ron's a good man, but we're going in a tougher direction. We want to go in a tougher direction. Reporter: And the purge at homeland security continued today, with removal of the head of the secret service, Randolph Alles. It comes with the president clearly frustrated that his get-tough policies have failed so far to stem the surge of migrants at the southern border. Our country is full, our area is full, the sector is full. We can't take you anymore. I'm sorry, can't happen. So, turn around. That's the way it is. Reporter: The numbers are stark. Officials estimate as many as a million undocumented migrants could try to cross the border this year, double last year's total. Nearing the record high of the early 2000s. But back then, it was mostly single men looking for work. Today, it's mostly families. A real shift there. Terry Moran with us live tonight from the white house. And Terry, with all this unfolding, through are now at least ten senior members of the president's team by our count serving in an acting capacity. Reporter: That's right, and it's starting to cause concern. There is a federal law which limits how long someone can hold a position in that way, 210 days. But there are exceptions, including homeland security. President trump has said he likes the flexibility of having acting secretaries. One reason, he doesn't have to ask the senate for its advice and consent on its cabinet, as the constitution would normally require. Terry Moran tonight. Terry, thank you.
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