Unmanned drones are patrolling the U.S.-Mexico border in larger numbers in an effort to crack down on illegal immigrants.
Oct. 25, 2007 A Predator drone takes off on a U.S. Customs and Border Protection mission from Fort Huachuca, Ariz. The Federal Aviation Administration had been asked to issue flying rights for a range of pilotless planes to carry out civilian and law-enforcement functions but was hesitant to act for safety reasons. Six years later, there are now drones patrolling most of the U.S.-Mexico border, from Yuma, Ariz., to Brownsville, Tex. Ross D. Franklin/AP Buy Photo