I ran across one of these guys at Heathrow on July 8, 2005, the day after the London bombings. I was heading into the old T2 EU departures area and was eventually landing in Nice. There was one positioned behind each passport checker and they clearly were not stopping people randomly, rather based on physical characteristics. Being mid-20s and of Middle Eastern origin, its pretty clear what was on this guy's mind and I made it clear by the look I gave him that he was a racist idiot. He asked some questions and moved on.