President Trump continues to insist he did not lose the November 3 election, even as election officials around the U.S. from both parties say there’s no sign of widespread voter fraud or other irregularities. On Thursday, Trump proposed a wild conspiracy theory about election software company Dominion Voting Systems, tweeting that hundreds of thousands of votes for Trump were switched to Biden. There’s no factual basis for Trump’s claim.

The Department of Homeland Security wrote in a statement, joined by election officials around the U.S., “The November 3rd election was the most secure in American history. … There is no evidence that any voting system deleted or lost votes, changed votes, or was in any way compromised.” Reuters reports that Christopher Krebs, the top cybersecurity official at the Department of Homeland Security, has told associates that he expects to be fired for refusing to back Trump’s false conspiracy theories. Ahead of the election, he posted this YouTube video to a “rumor control” website set up by DHS’s Cybersecurity and Infrastructure Security Agency.

Christopher Krebs: “The election experience is designed to ensure that technology is not a single point of failure. And there are measures in place to ensure that you can vote and your vote is counted correctly. You should have confidence in the integrity of the process, and don’t overreact to claims that exaggerate the importance of insignificant events.”