Mr. Trump also announced he was tapping U.S. Customs and Border Protection (CBP) commissioner Kevin McAleenan to run DHS on an acting basis.
US Department of Homeland Security Secretary Kirstjen Nielsen (left) speaks with Border Patrol agents near a newly fortified border wall structure in California.
Nielsen travelled to the U.S. -Mexico border on Friday with Trump to participate in a roundtable with border officers and local law enforcement.
Venezuela's ANC strips Juan Guaido of parliamentary immunity
The opposition leader is also accused of inciting violence through street protests, and of receiving illicit funds from overseas . Revoking immunity from arrest is the latest in a series of moves by Maduro and his allies to pressure the opposition leader.
The National Immigration Law Center, which has battled the administration's policies in court, said on Twitter Sunday: "Nielsen presided over a [DHS] that showed a blatant disregard for our Constitution, civil rights, and human life". That Nielsen herself is gone now is maybe of little solace to the families still waiting to see their children again, but at least somebody is now feeling defeated within that administration... we can only hope.
He said in a statement, however, that she should not serve as a scapegoat, blasting Trump for "terrible and cruel policies".
It was unclear whether Nielsen resigned voluntarily or was asked to do so. CBS News first reported Nielsen's impending departure, which Mr. Trump announced after a 5 p.m. meeting with Nielsen at the White House.
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At the time, Cain said the allegations were incorrect but acknowledged "he had made mistakes in my life", according to Bloomberg . Axios also earlier reported Trump has decided to choose Cain to fill one of two vacancies on the seven-member Fed board.
For many, Nielsen has been the public face of Trump's shameful immigration policies, including those created to separate children from their families at the southern border.
In recent weeks, administration officials have been sounding the alarm over the increase in migrants at the southern border, underscoring the change in demographics as one of the reasons for the host of challenges they're facing.
Ms Nielsen, 46, has held the position since December 2017.
He had previously threatened to close the US-Mexico border if Congress and Central American governments did not act to stem a flow of migrants that saw Nielsen last week order an "emergency surge" of personnel to handle the situation.
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Fassi finished the 54-hole tournament at 6-under par, four shots behind defending NCAA champion Jennifer Kupcho of Wake Forest. Kupcho was even through 12 holes before coming on in a big way down the stretch, playing her last six holes in 5 under.
She didn't then, and went on to become one of the public faces of a controversial policy that separated undocumented children from their parents.