WASHINGTON — The Cybersecurity and Infrastructure Security Agency (CISA) is among the offices being permanently downsized as a result of the ongoing partial government shutdown, The Post has learned.

The RIFs (reductions in force), which started Friday, will fire many of CISA’s 2,540 employees as well as thousands more within the federal bureaucracy — after President Trump repeatedly threatened to target offices cherished by Democrats if the party’s senators refused to reopen the government.

In an indication of the possible scale of the RIF, CISA had planned to keep just 889 employees on duty during a shutdown while furloughing 65% of its workforce.

CISA, a component of the Department of Homeland Security, was led by Chris Krebs during Trump’s first term and dismissed Trump’s allegations of voter fraud in the 2020 election, thumbing their nose at the president’s objection to mail-in ballots and calling it “the most secure in American history.”

One administration source told The Post that CISA had pumped out “disinformation.”

Other agencies and departments being impacted by the RIFs include the EPA, the Commerce Department, the Education Department, the Interior Department,  the Treasury Department, the Department of Health and Human Services and the Department of Housing and Urban Development. 

White House budget director Russ Vought announced that permanent job reductions had begun on the 10th day of the shutdown after Senate Democrats again blocked a reopening of the government, with just three upper-chamber Democrats siding with Republicans.

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“The RIFs have begun,” Vought tweeted.

“It’s unfortunate that Democrats have chosen to shut down the government and brought about this outcome. If they want to reopen the government, they can choose to do so at any time,” an EPA spokesperson said.

An official at a different federal agency said Friday afternoon that the precise number of terminations and the names of those receiving a pink slip may not become known until early next week as departments await specific guidance from the White House Office of Management and Budget. 

The terminations won’t take effect for 60 days — potentially after the shutdown ends — pursuant to a mandatory notice period. 

“Russell Vought just fired thousands of Americans with a tweet,” Senate Minority Leader Chuck Schumer (D-NY) said in a statement. “Let’s be blunt: Nobody’s forcing Trump and Vought to do this. They don’t have to do it. They want to. They’re callously choosing to hurt people — the workers who protect our country, inspect our food, respond when disasters strike. This is deliberate chaos.”

Up to 750,000 federal workers are being furloughed each day during the shutdown, some of whom could be swept up in the permanent firings sought by OMB. 

In total, around 2 million people work for the federal government, excluding the military and the US Postal Service.

Senate Democrats have sought to use the shutdown as leverage to extend pandemic-era health insurance subsidies for policies purchased through Affordable Care Act Obamacare exchanges. 

The enhanced subsidies are set to expire Dec. 31 for about 22 million people. Some Republicans favor extension, but GOP leaders have demanded that a temporary seven-week funding bill pass before a healthcare deal.

Republicans have objected to a Democratic proposal that would restore nearly $200 billion over 10 years in subsidies for asylum seekers and hospital reimbursements for illegal immigrants.