President Trump officially on trial as impeachment proceedings kick off, Hillary Clinton unleashes on one-time rival Bernie Sanders, and first U.S. case of deadly mystery virus confirmed.

Watch “NBC Nightly News With Lester Holt” at 6:30 p.m. ET / 5:30 p.m. CT (or check your local listings).

1:20 Trump's Impeachment Trial Begins With Fierce Senate Battle

5:22 Mcconnell UnVeils Last-Minute Surprise In Rules Debate

6:19 Trump Calls Impeachment Trial A 'Hoax' At Devos Conference

7:03 Trump Clashes With Climate Activist Greta Thunberg At Devos

7:54 Ukraine's President Expected At Davos Summit Tomorrow

8:07 Opening Arguments Expected In Trump's Trial Tomorrow

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