DS returned from Ukraine last night (3rd time he's been there since the Russian Special Operations started). At JFK passport control he was taken to a side room. He says the prevalent language in the room was Russian. Officers told most people there that they are not being allowed into the US, but are not being told to go to Russia, just back to IST (where they connected) and figure out there where they go next.
He was questioned as to why he keeps on going to Ukraine (he also has a Russian visa on his passport, and was in Russia last year) and whether anyone tried recruiting him. He was put on the phone with someone who questioned him further, and was asked if he has any information to share.
I told him today that in the future if he's ever stopped he has the right to (and should) ask why he is being stopped, demand that people questioning him identify themselves, and not necessarily answer questions, especially over the phone.