In the second week of the U.S. government shutdown, the Centers for Disease Control and Prevention notified some 1,300 employees they would be laid off — then rescinded hundreds of those notices within hours, a person familiar with the matter said.

The Trump administration is set to lay off entire offices and hundreds of CDC workers as part of mass job cuts during the federal shutdown, four sources told Reuters on Saturday.

A crowd-sourced list from CDC employees, reviewed by Reuters, suggested several units, including the entire Washington office, were targeted for termination. Two sources within the CDC and two at other health agencies confirmed the list’s validity.