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Congressional investigators are looking into whether Attorney General Jeff Sessions had yet another undisclosed meeting with Russian Ambassador Sergey Kislyak during the 2016 presidential campaign, Democratic and Republican aides and intelligence officials told CNN Wednesday.

They are specifically trying to determine if a private meeting took place between Sessions and Kislyak on April 26, 2016, at Washington, D.C.'s Mayflower Hotel. That day, candidate Donald Trump gave his first major foreign policy speech at the hotel, and both Sessions, then a Republican senator from Alabama, and Kislyak attended a reception prior to his address. Sessions, who has previously failed to disclose meetings he held with Russian officials, has been asked to hand over additional information, including his schedules. After saying during his confirmation hearing that he "did not have any communications with the Russians" during the campaign, it came out that Sessions did in fact meet with Kislyak twice; Sessions later said he didn't think he needed to share this information because the meetings took place as part of his Senate duties.