PORTLAND, Maine (AP) — Two members of Maine's congressional delegation are concerned about the forced resignation of Attorney General Jeff Sessions less than 24 hours after the midterm elections.

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GOP Sen. Susan Collins said it's imperative that the administration doesn't impede special counsel Robert Mueller's investigation into potential coordination between the president's Republican campaign and Russia.

Democratic Rep. Chellie Pingree echoed that sentiment.

She said she and Democrats who are taking control of the House "will be watching to ensure that this isn't an attempt by President Trump to interfere with the Mueller investigation."

Sen. Angus King also expressed concern.

Trump had criticized Sessions for recusing himself from Mueller's investigation.

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Trump announced in a tweet that he was naming Sessions' chief of staff Matthew Whitaker as acting attorney general. Whitaker has criticized Mueller's investigation.