Chris Krebs, a lifelong Republican, was put in charge of the agency handling election security by President Trump two years ago. When Krebs said the election was the country's most secure ever, Mr. Trump fired him. Now, Krebs speaks to Scott Pelley.

Though the transition has begun, President Trump remains largely holed up in the White House tweeting false accusations of a rigged election from behind a crumbling wall of lawsuits. No legal challenge, no recount, no audit has changed the outcome in any state. Mr. Trump's claim that millions of votes were deleted or switched is denied by the official he chose to secure the nation's election systems. Christopher Krebs called the 2020 vote "the most secure in American history" which promptly got him fired. Tonight, in his first interview since he was dismissed, Krebs tells us why he believes the vote was accurate and why saying otherwise puts the country in danger.

Chris Krebs: I have confidence in the security of this election because I know the work that we've done for four years in support of our state and local partners. I know the work that the intelligence community has done, the Department of Defense has done, that the FBI has done, that my team has done. I know that these systems are more secure. I know based on what we have seen that any attacks on the election were not successful.