Over the past 18 months, Southern Pacific trains in ’the area have been hit more than 100 times, at a cost of nearly $1 million. The bandits use assorted tactics. They’ve disabled switches to divert trains and stretched colored material in front of a trackside signal to make a green or yellow light appear red. The border patrol, local police and the railroad have fought back with everything from Wild West maneuvers to space-age moves. They’ve chased the robbers on foot and horseback, pursued them with helicopters and tracked them with night-vision surveillance scopes. But the attacks continue.

“Nowhere else is a working area so close to the border and so opportunistic,” says Dale Bray, a railroad police lieutenant. Mexico’s recent economic crisis has driven thousands more than usual to the border in search of jobs. At the same time, the U.S. Border Patrol has run a highly successful campaign that has stopped illegal immigrants from swarming into the El Paso area. Since most haven’t been able to cross over, they have settled in communities like Anapra. Two years ago Anapra was a tiny collection of cardboard shacks with no running water; now the population is 40,000 and crime is rampant. Overburdened Mexican police have few resources to devote to computers-or frozen fish–that have disappeared from Southern Pacific freight trains.

United States authorities want to build a 1.3-mile chain-link fence. The Mexican government has tentatively agreed, but immigrant advocates are opposed. So are Anaprans, who have erected a sign on the border that protests, in Spanish and English, “the wall of Berlin.” Good fences, no matter where, do not make good neighbors.