By Leah Douglas, Marisa Taylor and Julie Steenhuysen WASHINGTON (Reuters) -The Trump administration began mass layoffs of 10,000 staffers at U.S. health agencies on Tuesday, according to multiple sources familiar with the situation,

The cuts are part of a plan by President Donald Trump and billionaire ally Elon Musk to shrink staffing levels in federal agencies.

The moves, which the sources said are taking place at the National Oceanic and Atmospheric Administration and the Department of Energy, are the first evidence the administration of U.S. President Donald Trump is following through on a plan announced in his first day in office to recategorize tens of thousands of government workers to facilitate layoffs and remove career civil servants that may oppose its policies.