Republican presidential nominee former President Donald Trump and South Dakota Gov. Kristi Noem dance to the song "Y.M.C.A." at a campaign town hall at the Greater Philadelphia Expo Center & Fairgrounds, Oct. 14, 2024, in Oaks, Pa. (AP Photo/Matt Rourke, file)

WASHINGTON (AP) — President Donald Trump on Thursday fired his embattled Homeland Security Secretary Kristi Noem, after mounting criticism over her leadership of the department, including the handling of the administration’s immigration crackdown and disaster response.

Trump, who said he would nominate Oklahoma Republican Sen. Markwayne Mullin in her place, made the announcement on social media after Noem faced a two-day grilling on Capitol Hill this week from GOP members as well as Democrats.

Noem’s departure marks a stunning turnaround for a close ally to the president who was tasked with steering his centerpiece policy of mass deportations. But she appeared to increasingly become a liability for Trump, with questions arising over her spending at her department and over her conduct in the aftermath of the shooting deaths of two protesters in Minneapolis earlier this year.

Trump said Noem “has served us well, and has had numerous and spectacular results (especially on the Border!).” He said he was making her a “Special Envoy for The Shield of the Americas,” a new security initiative that he said would focus on the Western Hemisphere.

Noem, who appeared at a law enforcement event in Nashville, Tennessee, moments after Trump’s announcement, did not address her ouster there. She read from prepared remarks and was not asked by attendees about the development.

Later, in a social media post, she thanked Trump for the new appointment and touted her accomplishments as secretary.

“We have made historic accomplishments at the Department of Homeland Security to make America safe again,” she wrote.

White House press secretary Karoline Leavitt said the administration will work with the GOP-led Senate to get Mullin, whom she called “extraordinarily qualified,” confirmed to lead DHS “as soon as possible.”

Noem is the first Cabinet secretary to leave during Trump’s second term. Her tenure looked increasingly short-lived after hearings in Congress this week where she faced rare but blistering criticism from Republican lawmakers. One particular point of scrutiny was a $220 million ad campaign featuring Noem that encouraged people in the country illegally to leave voluntarily.

Noem told lawmakers that Trump was aware of the campaign in advance, but Trump disputed that in an interview Thursday with Reuters, saying he did not sign off on the ad campaign.

Noem has faced waves of criticism as she’s overseen Trump’s immigration crackdown, especially since the shooting deaths of the two protesters in Minneapolis at the hands of immigration enforcement officers. In the immediate aftermath of the deaths of Renee Good and Alex Pretti, Noem portrayed both of them as aggressors, contradicting widely viewed videos and descriptions of their deaths from bystanders. She declined to apologize for her description over two days of Congressional testimony.

The former South Dakota governor was also criticized over the way her department has spent billions of dollars allocated to it by Congress.

Her department, DHS, has been at the center of a funding battle in Congress over immigration enforcement tactics and has been shut down for 20 days, although many of the employees are continuing to work, often without pay.

Even before Noem’s appearance before key congressional committees this week, Republican lawmakers had been anticipating the secretary’s eventual ouster, particularly after her handling of the immigration enforcement crackdown in Minneapolis.

As they tried to end the ongoing Homeland Security shutdown, Senate Republicans had noted privately to Democratic senators that Noem was likely on her way out and that that should prompt Democrats to move forward with agreeing to fund the department again, according to two people familiar with the discussions.

Democrats did not see that as an actual concession by Republicans, considering Noem was becoming a political liability for the GOP, said the people, who spoke on condition of anonymity to discuss private negotiations.

Aside from immigration, Noem also faced criticism — including from Republicans — over the pace of emergency funding approved through the Federal Emergency Management Agency and for the Trump administration’s response to disasters.

Critics welcomed Noem’s departure. Minneapolis Mayor Jacob Frey wrote “good riddance” on social media, a sentiment echoed by Senate Democratic Leader Chuck Schumer.

Some immigration activists questioned whether her departure would change the execution of an immigration agenda that they fundamentally disagree with.

“This is not accountability, just a reshuffling of the enablers of the agenda of President Trump,” said Vanessa Cárdenas, executive director of America’s Voice, an advocacy group. She said Noem’s tenure was “marked by cruelty.”