The Pentagon expects to send 1,500 troops to the nation's borders with Canada and Mexico to assist Customs and Border Protection operations.
A would-be impostor was prevented from entering the US when a new facial recognition system spotted something that human inspectors would have missed.
Plans by the Obama administration to crack down on undocumented immigrants from Central America is creating a nervous atmosphere among several communities.
"Virtual Fence” links underground sensors, radar towers, and other networks into an integrated invisible surveillance system at the US - Mexico border.
U.S. Customs and Border Protection will begin capturing facial and eye scans of foreigners entering the country at San Diego's Otay Mesa.