JEFFERSON CITY, Mo. — Missouri Attorney General Andrew Bailey, a Republican who has been an ardent backer of President Donald Trump, said Monday that he is resigning to take a leadership position at the Federal Bureau of Investigation.

The move is the latest in a series of changes at the FBI under Director Kash Patel. Numerous senior officials, including top agents in charge of big-city field offices, have been pushed out of their jobs, and Justice Department officials have sought the names of agents who participated in investigations related to the Jan. 6, 2021, riot at the U.S. Capitol.

Bailey said he is stepping down effective Sept. 8 to serve as the FBI’s co-deputy director, alongside Dan Bongino. Missouri Gov. Mike Kehoe is to announce a new appointee as attorney general on Tuesday.

“My life has been defined by a call to service, and I am once again answering that call, this time at the national level,” Bailey said in a statement.

In a little over two-and-a-half years in the job, Bailey pursued numerous lawsuits challenging former President Joe Biden’s administration on an array of policies, including immigration actions,student loan forgiveness,environmental rules,gun safety initiatives and transgender rights measures.

He also threatened legal action against private gyms over bathroom policies, demanded that public schools ban drag shows and sued New York state, claiming that Trump’s 2024 hush money criminal trial was “overt meddling” in the 2024 election that limited Missouri voters’ information.

Most recently, Bailey’s office has defended the state’s anti-abortion regulations in the face of a voter-approved constitutional amendment establishing a state right to abortion.

Earlier this year, Bailey’s office won a $24.5 billion award against China for the COVID-19 pandemic in a case that originally was filed by his predecessor, Eric Schmitt, who won election to the U.S. Senate in 2022.

Bailey was serving as general counsel to Republican Gov. Mike Parson when his boss appointed him to replace Schmitt. An Army veteran, Bailey won a full four-year term as attorney general last November.