An executive at the U.S. Internal Revenue Service told staffers Thursday about 6,000 employees would be fired, a person familiar with the matter said, in a move that would eliminate roughly 6% of the agency's workforce in the midst of the critical tax-filing season.

The cuts are part of President Donald Trump's radical downsizing effort that has targeted bank regulators, forest workers, rocket scientists and tens of thousands of other government employees. The effort is being led by tech billionaire Elon Musk, Trump's biggest campaign donor.

The layoffs at the IRS largely target workers at the agency who were hired as part of an expansion under former Democratic President Joe Biden, who had sought to expand enforcement efforts on wealthy taxpayers. The agency now employs roughly 100,000 people, up from 80,000 when he took office.

Independent budget analysts estimate the expansion could boost government revenues and help narrow trillion-dollar budget deficits. Trump's Republicans say the expansion would lead to more harassment of ordinary American taxpayers.

The workers being cut are in their probationary period and enjoy fewer protections than career employees.

The IRS has taken a more careful approach to downsizing than other agencies given that it is in the middle of its busiest period, with the April 15 tax filing deadline just two months away.

The 2025 tax filing season opened on January 27, with the IRS expecting over 140 million individual tax year 2024 returns by the federal filing deadline.

The dismissals target revenue agents, customer-service workers, specialized auditors and IT specialists across all 50 states, Puerto Rico and Washington, D.C., according to people familiar with the matter.

The IRS will retain several thousand probationary employees deemed critical for processing tax returns, including those involved in supporting and advocating for taxpayers, one source said.

The White House has not said how many of the nation's 2.3 million civil-service workers it wants to fire and has given no numbers on the mass layoffs. Roughly 75,000 took a buyout offer last week.

The campaign has delighted Republicans for culling a federal workforce they view as bloated, corrupt and insufficiently loyal to Trump, while also taking aim at government agencies that regulate big business and collect taxes -- including those that oversee Musk's companies SpaceX, Tesla and Neuralink.

Musk's Department of Government Efficiency team has also canceled contracts worth about $8.5 billion involving foreign aid, diversity training and other initiatives opposed by Trump. Both men have set a goal of cutting at least $1 trillion from the $6.7 trillion federal budget, though Trump has said he will not touch popular benefit programs that make up roughly one-third of that total.

Democrat critics say Trump is exceeding his constitutional authority and hacking away at popular and critical government programs at the expense of legions of middle-class families.