The Department of Health and Human Services laid off employees Saturday evening across some of its biggest agencies — the Centers for Medicare and Medicaid Services, the Food and Drug Administration, and the Centers for Disease Control and Prevention, according to emails reviewed by Bloomberg News.

The notices Saturday indicated that layoffs would expand beyond prior reports of job cuts at the CDC and National Institutes of Health at a time when President Donald Trump’s administration is seeking to shrink the size of the federal government.

Workers cut over the weekend included employees that evaluate the safety of medical devices and conduct oversight of Affordable Care Act exchanges, according to memos reviewed by Bloomberg.

The full scope of the cuts remains unclear. Neither HHS nor the White House, CMS, CDC nor FDA responded to requests for comment on Sunday.

The notices were contained in emails with the subject line “Read this email immediately” that arrived for some around 7 p.m. on Saturday night, according to a person who received one. The letters stated that the employees were “not fit for continued employment because your ability, knowledge and skills do not fit the agency’s current needs, and your performance has not been adequate to justify further employment at the agency.”

The emails told workers they will be placed on administrative leave and receive four weeks of pay and were signed by Jeffrey Anoka, the acting head of human resources at HHS.

The notices follow an executive order Trump signed on Tuesday requiring federal agencies to enact “large-scale” employee cuts.

Robert F. Kennedy Jr. was sworn in as the head of HHS on Thursday, but the heads of the FDA, CMS, and CDC have not yet been confirmed.