(CBS NEWS) — Department of Homeland Security Secretary Kirstjen Nielsen is resigning, President Trump announced in a tweet Sunday.

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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Customs and Border Protection Commissioner Kevin McAleenan will serve as acting DHS secretary, the president announced.

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“Secretary of Homeland Security Kirstjen Nielsen will be leaving her position, and I would like to thank her for her service,” Mr. Trump tweeted Sunday. “…I am pleased to announce that Kevin McAleenan, the current U.S. Customs and Border Protection Commissioner, will become Acting Secretary for @DHSgov. I have confidence that Kevin will do a great job!”

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