WASHINGTON — (CNN) The chief of US Border Patrol has departed the agency, Customs and Border Protection said in a statement Thursday — the day after President Donald Trump signed executive orders aimed at beefing up border security.

It was not clear whether he had resigned or was asked to leave.

Border Patrol Chief Mark Morgan’s departure is not uncommon in a presidential transition. The head of the Transportation Security Administration, Peter Neffenger, also left in the transfer of power. He had been willing to stay on, but the Trump administration had not asked him to until he had already made other plans.

Morgan’s resignation comes on the heels of Trump’s move to begin fulfilling his campaign promises on border security and immigration with a pair of executive orders Wednesday that ordered the construction of his pledged wall along the border with Mexico and asked for an increase of 5,000 Border Patrol agents, among other actions.

Customs and Border Protection acting-Commissioner Kevin McAleenan issued a statement thanking Morgan for his service and wishing him well.

“I want to thank Mark Morgan for his unwavering dedication to our border security mission, and recognize his life-long career in service to the nation,” McAleenan said. “Mark Morgan’s career spans more than 31 years of faithful service to the nation, including service in the U.S. Marine Corps, as a local deputy sheriff and police officer, 20 years in the FBI, as Assistant Commissioner of CBP’s Office of Internal Affairs, and, finally, as

Chief of the U.S. Border Patrol. I wish him every success in the future.”

Customs and Border Protection is a division of the Department of Homeland Security that manages US borders and entry points.

Border security has been a central theme of Trump’s throughout the campaign, with preventing illegal immigration at the Southern border being a key focus.

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