Magnus was told on Wednesday by Homeland Security Secretary Alejandro Mayorkas that he should either resign or be dismissed and, so far, the CBP chief has refused to step down, according to the four people.

Some executive assistant commissioners at CBP have indicated they would leave the agency if Magnus does not resign, according to one of the current DHS officials and the former DHS official.

Mayorkas has since shifted Magnus’ duties and responsibilities to his deputy secretary, John Tien, and has deputy CBP commissioner Troy Miller, a career government official, running the agency’s day-to-day operations, according to three of the people.

One of the current officials said all CBP decisions now must first go through the DHS front office. In addition, all of Magnus’ direct reports are reporting to Tien and Miller, according to one of the other officials.