Trump says he’s replacing Homeland Security Secretary Kristi Noem

President Donald Trump says he’s replacing his embattled Homeland Security Secretary Kristi Noem and will nominate in her place Oklahoma Republican Sen. Markwayne Mullin.

Trump made the announcement on social media on Thursday, two days after Noem faced a grilling on Capitol Hill from GOP members as well as Democrats.

Trump says he’ll make Noem a “Special Envoy for The Shield of the Americas,” a new security initiative that he said would focus on the Western Hemisphere.

Noem is the first Cabinet secretary to leave during Trump’s second term. Noem’s departure caps a tumultuous tenure overseeing immigration enforcement tactics that have been met with protests and lawsuits.

Noem has faced waves of criticism as she’s overseen Trump’s immigration crackdown, especially since the shooting deaths of two protesters in Minneapolis at the hands of immigration enforcement officers. The former South Dakota governor was also criticized over the way her department has spent billions of dollars allocated to it by Congress.

Frustrations over Noem’s execution of the Republican president’s hard-line immigration agenda — particularly her leadership after the shooting deaths of the two U.S. citizens in Minneapolis — as well as her handling of disaster response, paved the way for her downfall. She faced blistering criticism from Democrats, and some Republicans, in Congress hearings this week over those issues and others.