Trump Fires Christopher Krebs, Official Who Disputed Election Fraud Claims

President Trump on Tuesday night fired his administration’s most senior cybersecurity official responsible for securing the presidential election, Christopher Krebs, who had systematically disputed Mr. Trump’s false declarations in recent days that the presidency was stolen from him through fraudulent ballots and software glitches that changed millions of votes.

The announcement came via Twitter, the same way Mr. Trump fired his defense secretary a week ago and has dismissed other officials throughout his presidency. The president seemed set off by a statement released by the Department of Homeland Security late last week, the product of a broad committee overseeing the elections, that declared the 2020 election “the most secure in American history.”

“The recent statement by Chris Krebs on the security of the 2020 Election was highly inaccurate,” Mr. Trump wrote a little after 7 p.m., “in that there were massive improprieties and fraud — including dead people voting, Poll Watchers not allowed into polling locations, ‘glitches’ in the voting machines which changed votes from Trump to Biden, late voting, and many more.” He said Mr. Krebs “has been terminated” as director of the Cybersecurity and Infrastructure Security Agency, a post to which Mr. Trump himself had appointed him.

Mr. Krebs, 43, a former Microsoft executive, has been hailed in recent days for his two years spent preparing the states for the challenges of the vote, hardening systems against Russian interference and setting up a “rumor control” website to guard against disinformation. But much of that disinformation came not from Moscow, but from the White House.

Only two weeks ago, on Election Day, Mr. Krebs’s boss, Chad F. Wolf, the acting secretary of homeland security, had praised Mr. Krebs’s work, including the “rumor control” effort. But behind-the-scenes efforts by administration officials to keep Mr. Trump from firing Mr. Krebs apparently failed.

Mr. Krebs started telling colleagues he expected to be fired after the election as early as June, when the president started claiming that mail-in voting would be “rigged.” The refusal by Mr. Krebs and his agency to back up the president’s claims put him on a list of disloyal officials, Mr. Krebs believed, that included Mark T. Esper, who was fired as secretary of defense shortly after the election; Christopher A. Wray, the F.B.I. director; and Gina Haspel, the director of the C.I.A. Mr. Wray and Ms. Haspel remain in their jobs.

In recent weeks, Mr. Krebs drew the president’s ire again with his refusal to echo Mr. Trump’s conspiracy theories about software glitches and dead people voting. Quite the contrary: Within hours of Mr. Trump tweeting false reports that millions of Trump votes were deleted, Mr. Krebs joined election officials in calling the 2020 election “the most secure in American history.”