The Pentagon announced Friday it plans to ultimately fire five to eight percent of the military’s approximately 950,000 civilian employees, with an initial tranche of 5,400 probationary workers who don’t have “mission-critical” roles expected to be terminated next week.

The dismissals will begin next week, officials said, and could expand to include tens of thousands of other workers throughout the Defense Department.

The Pentagon said on Friday it would start firing about 5,400 civilian employees who were on probation, the first moves by President Donald Trump's administration at the department to make good on its promise to reduce the federal workforce.