Former acting attorney general Sally Q. Yates warned the White House that national security adviser General Michael Flynn may be vulnerable to Russianblackmail, the Washington Post reported on Monday.

Yates had delivered the message late last month amid worries about Flynn’s communication with the Russian ambassador in Washington, according to the report, which cited unnamed current and former U.S. officials.

It wasn’t clear, the Post reported, what White House Counsel Donald McGahn had done with Yates’ information.

Read the full report here.

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