A second area of focus was what happened during the event. The source said questions also focused on meetings Trump had with Russian business people or government officials, leading the source to believe the investigators were probing the possibility of “kompromat,” or compromising material, on Trump.

Along these lines, the source said, investigators were interested in logistics surrounding Trump’s hotel room in Moscow: Who was there? Who would have access to it? Who was in charge of security? Who was moving around with him during the trip?