Trump fires Cisa boss - as it happened

• In a tweet firing Chris Krebs, Trump repeated baseless fraud claims
• Court rules officials did not improperly block Trump's campaign from observing counting of mail-in ballots
• Senator Chuck Grassley tests positive for Covid-19
• Judy Shelton's Fed nomination fails to advance
• Biden's names first White House appointments
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1.46am GMT

Here's a recap, from me and Joan E Greve:

Related: Trump fires head of US cybersecurity agency that refuted voter fraud claims

1.36am GMT

Mark Warner, a Democratic senator of Virginia and co-chair of the Senate cybersecurity caucus, said Krebs is an extraordinary public servant and exactly the person Americans want protecting the security of our elections".

It speaks volumes that the president chose to fire him simply for telling the truth," he said, echoing many of his Democratic colleagues.