Failed 2016 Democrat presidential candidate Hillary Clinton said Monday that the departure of Homeland Security Secretary Kirstjen Nielsen won’t end what she described as the Trump administration’s “dehumanization and cruelty” toward migrants that reach the U.S.-Mexico border.

“Let’s be clear: This administration’s dehumanization and cruelty toward migrants will not stop after Kirstjen Nielsen leaves office. It is their principal policy,” Clinton wrote in a social media post.

Clinton’s remarks follow Nielsen’s Sunday evening resignation, which was first reported by CBS News and later confirmed by President Donald Trump. “Secretary of Homeland Security Kirstjen Nielsen will be leaving her position, and I would like to thank her for her service,” the president said. “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!”

Nielsen’s departure as comes as U.S. Customs and Border Protection (CBP) struggle with a surge in illegal immigration at the Southern border and the expansion of the Catch and Release policy, which allows migrants to enter the U.S. while they await a hearing in an immigration court.

Breitbart News’ John Binder reported:

During Nielsen’s tenure as DHS secretary, illegal immigration has increased nearly every month over the last year and a half. Simultaneously, the Trump administration has yet to construct a border wall on new land at the southern border that did not previously have barriers built by the Bush and Obama administrations. Most recently, officials with the National ICE Council accused Nielsen of “grossly” mismanaging DHS and failing to acknowledge that the agency had been operating an expanded Catch and Release policy for border crossers and illegal aliens for months.

Nielsen previously served in the Bush administration overseeing a crisis team following the destruction of New Orleans, Louisiana, by Hurricane Katrina in 2005.

During Nielsen’s tenure, the Trump administration introduced the “zero tolerance” immigration policy, which sought the prosecution of every alleged border crosser. An unintended consequence of the policy resulted in the separation of families at the border, which she repeatedly called on Congress to address. President Trump signed an executive order in June 2018 to halt the practice of separating migrant families apprehended at the border.