President Donald Trump announced the removal of Kristi Noem from the position of Secretary of Homeland Security in a Truth Social post on Thursday.
He replaced her with Senator Markwayne Mullin of Oklahoma, who will take over the role on March 31.
Mullin is a successful business owner and working cow calf rancher, with a background in mixed martial arts.
He served 10 years in the U.S. House of Representatives and is an enrolled member of the Cherokee Nation.
Mullin is married to Christie and has six children, and has a net worth of around $65 million.
Noem's change comes after she faced bipartisan rebukes during congressional hearings, reportedly over a $200 million advertising campaign.
