STALKING illegal immigrants along the US-Mexican border is usually more like a game of tag than cops and robbers for agents of the United States Border Patrol.
Violence by illegals is rare. Most of the Mexicans and Central Americans apprehended face a few hours of inconvenience before they are sent back across the border. Thus they normally aren't inclined to tangle with arresting agents, who during nighttime roundups feel secure enough to single-handedly haul as many people as can squeeze into their green Chevy Suburbans.
But beefed up enforcement around El Paso, Texas, in what is called Operation Hold the Line, is changing the pattern.
In recent weeks, agents there have taken fire from train bandits and drug smugglers. They've encountered rock- throwing gangs. They've discovered spike boards left to puncture patrol vehicle tires. Statistics on border violence were never kept before. But since the fiscal year began last October, El Paso Sector agent Doug Mosier has tallied more than 50 incidents of aggression.
Despite increased funding and more agents, other Border Patrol sectors along the 2,000 mile border report only sporadic confrontations. Human rights groups claim the victims of violence are more likely to be the immigrants than the Border Patrol agents. Last month, a study by Human Rights Watch -- Americas, a Washington-based group, alleged that the agents are responsible for dozens of beatings, shootings, rapes, and even deaths. The Border Patrol says out of 1.3 million people caught last year, there was 1 complaint per 17,000 apprehensions.
Nonetheless, violence against agents is apparently on the rise near El Paso.
The epicenter is Anapra, a mushrooming shantytown with an estimated 15,000 to 40,000 residents. It lies smack against the border in a narrow valley between two mountains just west of El Paso and across from Sunland Park, N.M. As Operation Hold the Line has reduced illegal crossings near El Paso, the flow has shifted to Anapra. The area now accounts for three-fourths of Border Patrol apprehensions in the El Paso sector.
And the traffic isn't just northbound. So many Mexicans were returning to their country via Anapra that Mexican Customs erected an inspection station there, even though it's not an official US-Mexico border crossing.
On the US side is ''a real montage of jurisdictions'' that make law-enforcement coordination more difficult, says El Paso Sgt. Bill Pfeil. Some of the terrain is outside the city in El Paso County. Other falls inside New Mexico's Dona Ana County or Sunland Park.
And through it all, sometimes 25 feet from the border, runs the Southern Pacific Railroad. The slow-moving trains are a constant target of the Mexican gangs. The bandits climb aboard, break into shipping containers, and toss the contents alongside the tracks for their comrades to retrieve.
''The problem has increased in recent years because of Anapra,'' says Southern Pacific spokesman Mike Furtney in San Francisco, who declined to be more specific. There's nothing to protect the trains ''but an imaginary line in the dirt.''
But Operation Hold the Line has generated frustration among criminal gangs operating in Anapra, Agent Mosier says. The increased enforcement is eating into the gangs' livelihood, causing them to strike back with unusual force.
Last month, Border Patrol agents were the first lawmen on the scene of a train robbery. They reportedly drew fire from the fleeing gang. Train robberies aren't unique to El Paso, Mr. Furtney says, ''but the April incident ''went a little beyond the ordinary.''
To deal with Anapra, the Border Patrol proposes sealing it off as it has done elsewhere. Using steel sheets that the military uses for landing mats, the US could erect a 10-foot-high fence. A 1.3-mile fence would cost just $25,000, because the military would donate materials and labor, Mosier says. The plan awaits final approval in Washington.
Besides bandits living in Anapra, there is still the threat from drug smugglers. Two days after the train robbery incident, agents near Fort Hancock, east of El Paso, captured a Suburban loaded with 847 pounds of marijuana. But they also exchanged fire with the smugglers, who retreated into Mexico. Mosier says Mexican police later found more than 100 shell casings from automatic weapons fired by the smugglers.