Sanders has served as the agency's acting head since the previous commissioner Kevin McAleenan left to head the Department of Homeland Security in April. His departure comes as CBP faces growing criticism of its treatment of detained migrant children, though The Washington Post's Nick Miroff cites a DHS official in saying that isn't the cause of Sanders' resignation.
CBP has long faced scrutiny over its treatment of migrants at the border, especially under President Trump's administration. That ramped up last week amid reports that nearly 300 minors, some as young as 2 and half years old, were facing unsanitary conditions at a Clint, Texas detention facility. Most of them had been transferred out of the facility and to a tent camp on Monday, but on Tuesday, CBP reportedly moved 100 of those children back.
Before heading CBP, Sanders was the agency's chief operating officer and is a close ally of McAleenan. Sanders offered his resignation to McAleenan on Monday, saying it would be effective July 5, The Wall Street Journal notes. He didn't elaborate on his reasons for resigning. Kathryn Krawczyk