Donald Trump announced on Thursday the dismissal of Homeland Security Secretary Kristi Noem, one of the leading figures in the US president's policy of mass deportations of immigrants.

The minister has been given a "special envoy" mission for Latin America, Donald Trump said on his Truth Social network, saying he wanted to replace her from March 31 with Republican Senator Markwayne Mullin.

This nomination will need to be approved by the Senate, where Republicans hold a majority.

According to the press, Donald Trump, who praised the "numerous and spectacular results (particularly on the borders)" obtained by Kristi Noem, reportedly made his decision after tense parliamentary hearings with the minister, her first since the deaths in January in Minneapolis of two protesters against immigration police (ICE).

He was particularly incensed that Ms. Noem had assured a Senate and then a House of Representatives committee that she had obtained his approval for a $220 million advertising campaign aimed at encouraging immigrants to return to their country of their own accord without waiting to be deported, several media outlets explain.

She personally appeared in this campaign, including on horseback in front of the mythical Mount Rushmore in South Dakota, the state where she was born.

- "Good riddance" -

Donald Trump described his successor as "a MAGA warrior".

Markwayne Mullin told reporters he wanted to "build on the successes" of Kristi Noem, but also on "things that perhaps didn't go as planned," without further elaboration.

The outgoing minister thanked Donald Trump on X for her new position.

She claimed "historic successes", asserting in particular that, since the beginning of the Republican president's second term, "more than three million undocumented immigrants have left the United States", statistics disputed by immigration specialists.

"Kristi Noem is gone. Good riddance, she was a disaster," House Speaker Hakim Jeffries said in a statement to the press. "But let's be clear: a change of person is not enough, we need a change of policy," he warned.

"She should have been fired a long time ago," said Democratic Senator Adam Schiff. "It is both telling and disturbing that what appears to have cost her her job was her public relations campaign" rather than the actions of the immigration police, he emphasized.

After presidential national security advisor Mike Waltz, ousted in May following the inadvertent inclusion of a journalist in a confidential Signal chat group, Kristi Noem is the second top official fired from the Trump administration.

- "Fame" -

In Congress this week, the minister was questioned in particular about the conditions under which this advertising contract was awarded, as well as her hasty presentation of the two protesters, recently killed by federal police in Minneapolis, as "domestic terrorists".

Invited by Democratic lawmakers to apologize to their families and correct her remarks, Kristi Noem merely offered her "condolences" for their "tragic" deaths, denying that she had called them "terrorists".

In a rare move, the minister faced criticism from several Republican elected officials, some of whom even called for her resignation.

"How do you reconcile your concern about waste, which I share, with the fact that you have spent $220 million on television commercials in which you feature very prominently?" Republican Senator John Kennedy asked him.

The minister replied that the advertising campaign had been "effective".

"Effective for your public profile," the senator told him.

The Department of Homeland Security has been in a state of budgetary paralysis since mid-February, with Democrats demanding that the practices of federal agents be reformed from top to bottom.

Donald Trump has made the fight against illegal immigration an absolute priority, referring to an "invasion" of the United States by "criminals from abroad" and communicating extensively about the deportations of immigrants.