Could they be known ‘persons of interest’ for lack of a better term, and the FBI just connected the names to people who have crossed the boarder. They do not take pictures at border crossings.
And why the @#$! not?!
They take pictures of citizens going about their daily lives in DC and elsewhere, they have taken pictures of citizens participating in peaceful demonstrations in DC, and they plan on taking pictures of pro-life citizens when they participate in the March For Life next month. If US citizens are photographed in the name of Homeland Security, what in the Sam Hill is going on within our "security" agencies that they don't take the intelligent course and do the same thing at our borders? Sheesh!