Donald Trump is removing the director of the US Secret Service, the White House said, a day after it was announced Homeland Security Secretary Kirstjen Nielsen would leave her job.
The dismissal of Secret Service Director Randolph "Tex" Alles comes amid major leadership changes at the sprawling Department of Homeland Security (DHS). The Secret Service director reports to the Homeland Security secretary.
The first sign of the overhaul came late on Thursday, when the US president abruptly pulled his nomination of Ron Vitiello as director of US Immigration and Customs Enforcement, part of DHS. Mr Trump described that move as part of a policy change "going in a tougher direction."
White House spokeswoman Sarah Sanders said James Murray, a career Secret Service agent, will take over the Secret Service in May.
A senior administration official said Mr Trump asked for Ms Nielsen's resignation when the two met at the White House on Sunday. The president also announced that Kevin McAleenan, the US Customs and Border Protection commissioner, would become acting DHS secretary.
One official described the firings to CNN as "a near-systematic purge" at the Department of Homeland Security. Fox News cited sources as saying Mr Alles' removal was part of a transition in leadership at DHS.
The removal of Mr Alles marked the latest in a long line of firings and resignations of senior officials in the Trump administration, a list that has included the secretaries of state, defense, homeland security, interior, veterans affairs and health and human services, the attorney general and numerous senior White House aides.
Mr Trump, seeking re-election in 2020, has taken a hard line toward immigration since becoming president in January 2017, and the issue may be a central theme in next year's race.
Ms Nielsen, who oversaw Trump's bitterly contested immigration policies during her tumultuous 16-month tenure, resigned amid a surge in the number of migrants at the border with Mexico.
Her departure had been long rumoured particularly after criticism of the administration's 2018 family separation policy at the border with Mexico and as US border officials estimated that 100,000 migrants were apprehended at the southern border in March, the highest level in a decade.
Trump was so frustrated about the increase that he announced he would cut off US aid to Guatemala, Honduras and El Salvador.
Mr Alles, appointed to the post by Trump in April 2017, previously held a senior job at the US Customs and Border Protection agency and served 35 years in the U.S. Marine Corps before retiring as a major general in 2011.
The Secret Service is responsible for protecting senior US officials including the president and vice president, former presidents and visiting heads of state. The agency also is charged with enforcing counterfeiting laws and safeguarding the payment and financial systems of the United States.
CNN reported that Mr Trump in recent weeks empowered his hard-line conservative aide Stephen Miller to lead the administration's border policies and quoted the official as saying Mr Miller's plans amount to a wholesale decapitation of the Department of Homeland Security's leadership.
L Francis Cissna, director of the US Citizenship and Immigration Services agency, and department General Counsel John Mitnick are also expected to be out of their jobs soon, CNN reported.
The Secret Service also came under scrutiny last week after a Chinese woman carrying electronic devices bluffed her way through security checks at Trump's Mar-a-Lago resort in Florida.