The Washington Post is reporting that a current senior White House adviser is under scrutiny as part of an investigation into possible coordination between the Trump campaign and Russia.

The newspaper is citing unidentified people familiar with the investigation. The adviser under scrutiny is not named, but described as someone close to Trump.

The Post says the revelation comes as the investigation appears to be entering a more open and active phase, with investigators conducting interviews and using a grand jury to issue subpoenas.

Current administration officials who have acknowledged contacts with Russian officials include Trump’s son-in-law, Jared Kushner, Attorney General Jeff Sessions and Secretary of State Rex Tillerson.

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