As President Donald Trump’s administration continues to be heavily criticized at home and abroad for its treatment of migrant children — six of which died while in U.S. immigration custody — the acting Customs and Border Protection Commissioner, John Sanders, announced his resignation on Tuesday.

“As some of you are aware, yesterday I offered my resignation to Secretary McAleenan, effective Friday, July 5,” wrote Sanders in an email to CBP employees.

The news of Sanders departure, first reported by The New York Times, lays bare the administration’s inability to care for the migrant children adequately and deal with the influx of migrants crossing the border.   

“Although I will leave it to you to determine whether I was successful, I can unequivocally say that helping support the amazing men and women of CBP has been the most fulfilling and satisfying opportunity of my career,” he continued.

In recent days, the administration, and Trump in particular, has been condemned over migrant children being kept in “filthy” and “overcrowded” conditions.  

“Ripping children from their parents, putting babies in cages, denying children soap, toothbrushes, and blankets is cruel and sadistic. It is positively evil that this is all to create chaos in our country and score points with Trump's political base. Children will not be safe until these camps are closed,” Jess Morales Rocketto, Chair of Families Belong Together, said in a statement. 

Sanders assumed the role of CBP Chief after Kevin McAleenan, the agency’s former head, became the acting Department of Homeland Security secretary following Kirstjen Nielsen's ouster in April.

His resignation takes effect on July 5.