By Bob Ortega The Republic | azcentral.com Fri Feb 21, 2014 10:57 PM

After a federal law-enforcement team discovered a 481-foot tunnel crossing the border into Nogales on Feb. 10, agents swooped in to seize 636 pound of marijuana and a half-pound of heroin and made three arrests.

Five days later, 13 undocumented migrants used the same tunnel to cross into Arizona from Nogales, Sonora. Border Patrol agents apprehended the crossers after they came out of the house where the tunnel ended. Reporters for the newspaper Nogales International, which first reported the crossing, said they found the house’s front door open a day later and no agents in sight.

“Just because they didn’t see agents doesn’t mean it wasn’t monitored,” Border Patrol spokesman Vic Brabble said Friday. “It’s under constant surveillance. Our understanding is the other end is secured now.” Mexican authorities didn’t return calls for comment.

http://www.azcentral.com/news/arizon...drug-bust.html