border around arizona in a town of less than 100 people. >> i've been called everything in the book. i've been called a domestic extremist. >> reporter: the southern poverty law center says foley's group is made up of native extremists. he sees the flow of drugs, undocumented migrants and the wide open spaces of the border as the country's biggest threat. along the 2,000-mile southern border there is already 700 miles of fencing and barricades already in place. here in sass by, arizona, this steel see-through fence stretches for several miles. as you approach the end of town, it abruptly comes to an end as it stretches out into rugged, remote terrain in the arizona desert. >> i put the cameras about five minutes from the road. >> reporter: he relies on a collection of cameras he hides in the brush to catches the movements of drug smugglers. he often shares the videos and