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Good morning.

Here’s what you need to know:

• The Russia investigation.

President Trump acknowledged today for the first time publicly that he is under investigation in the expanding inquiry into Russian influence in the election.

He also appeared to attack the integrity of Rod Rosenstein, the deputy attorney general, who is in charge of the inquiry, and to accuse him of leading a “witch hunt.”

Members of the president’s transition team were ordered on Thursday to preserve documents and other materials related to the investigation, according to a memo obtained by The Times.