Cartels using Ariz. mountaintops to spy on cops

From nbcnews.com:

TUCSON, Ariz. — Hiking through rough Arizona desert terrain a few miles north of the Mexican border recently with a group of armed DEA agents, we were approached by a lone U.S. Border Patrol agent. He warned we should be careful up ahead, because two people believed to be spotters for a Mexican drug cartel had just been seen running down a ridge to elude U.S. authorities.

http://www.nbcnews.com/id/43096521/ns/nightly_news/t/cartels-using-ariz-mountaintops-spy-cops/from/toolbar