NOGALES, Ariz. -- Border Patrol agents are using new robot technology to catch illegal activities inside tunnels at the Arizona-Mexico border.
Agents in the Tucson sector will demonstrate Tuesday how so-called "tunnel robots" will be used to detect any tunnels that could be used by illegal border-crossers.
The agents will be joined by tunnel experts at a drainage tunnel in Nogales.
U.S. Customs and Border Protection said criminal organizations in Mexico are increasingly turning to tunnel systems as border security above ground tightens.
The agency said the tunnels are typically used to transport people, drugs, weapons and other illegal materials.
More than 75 such underground passages have been found along the border since 2008, concentrated largely in California and Arizona.