On a domestic flight DTW - XXX 2 years ago upon landing we were instructed to remain seated with our seatbelts fastened in a very strong voice. I'm sitting in 17C. Amazingly, everyone listened, probably because the tone on the PA was so unusual. After the door opened, 6 police boarded and came back glancing at me and the rest of row 17. I had an uneasy feeling in my stomach at this point, due to the unusual nature of the situation. Getting to row 17, they first glance down at me, and then at my seat letter -- then they shift their gaze to the other side. They pull the guy on the other side of the aisle next to me, 17D with not more than a few words, and they peacefully cuffed him and walked him off the plane.
I never could find in the papers what that was about. Made me wonder who was sitting next to me for the last 2 hours!