Authorities work to decipher meaning of an influx of Chinese. Catching Chinese illegals should be a low priority. They make excellent citizens: Generally law-abiding and hard-working. Chinese youths are to be found in universities, not street gangs

Amid an overall drop in arrests of illegal crossers at the U.S- Mexico border, an intriguing anomaly has cast new light on the global underworld of immigrant smuggling. Authorities report an almost ten-fold spike in arrests of clandestine migrants from China in the southern Arizona desert, the busiest smuggling corridor on the international line. The Border Patrol in the Tucson sector has caught at least 261 Chinese crossers this year, compared to an average of 32 during the past four years, officials say. “They are the main [non-Mexicans] we catch,” said Agent Juventino Pacheco of the Patrol’s international liason unit here. “Lately we have been catching more Chinese than Central Americans in Nogales.”

As agents find groups of exhausted Chinese migrants hiding in gulches and huddled in smuggling vehicles, the Border Patrol scrambles for the services of professional interpreters. The sector’s only Mandarin-speaking agent, a former Mormon missionary in China, has kept very busy.

The increase remains but a fraction of the overall activity at the Nogales station, which is the biggest in the entire Patrol and guards 31 action-packed miles abutting Nogales, Mexico. This year, the Tucson sector that encompasses the Nogales station recorded a total of 226,000 apprehensions — a 24% decline that reflects the impact of the U.S. economic crisis and tougher enforcement, officials say. The great majority of those arrested were Mexicans.

In the lexicon of the Border Patrol, Chinese immigrants belong to a rarefied category known as OTMs: Other than Mexicans. Although just a small percentage of border-crossers, OTMs are big business for smuggling gangs that overlap increasingly with Mexico’s violent drug mafias. Compared to Mexicans who pay about $1,500, smuggler fees for Central Americans and South Americans reach $6,000 for the trek across a sun-seared landscape, as dangerous as it is majestic. A group of bewildered Haitians intercepted in Tucson after three nights hiking in circles in a canyon had coughed up $10,000, with another $10,000 due on arrival in the Chicago area.

Chinese pay the most of all. They often work off fees between $30,000 and $70,000 over the course of several years as indentured servants in the sweat shops and kitchens of New York and other cities. Sophisticated Asian mafias organize long, intricate journeys. A typical route leads from Beijing to Rome to Caracas, Venezuela to Mexico City to the border, according to Matthew Allen, the chief agent of the Phoenix office of Immigration and Customs Enforcement. “It’s much more elaborate” than smuggling Latin Americans, Allen said. “Waiting in hotel rooms, calls on cell phones, code words. The trend [in increased arrests] stands out as apprehensions are going down overall.”

What explains the increase here? Does it reflect a major influx of Chinese illegals into the U.S.? Enforcement officials say it’s not clear. At the border, facts are elusive. Statistical barometers are imperfect. Differing interpretations, political spin and the mysteries of the criminal underworld complicate the picture. High-priced smugglers are better at dodging defenses, so it’s hard to assess the correlation between arrests, crossing rates and the number of illegal immigrants who succeed.

Chinese smuggling made headlines at its chaotic peak in the early 1990s. Fetid smuggling flotillas swarmed the coasts of Southern California, Mexico and Central America. Seven people died in June, 1993 when the ship Golden Venture ran aground in New York carrying 286 migrants, more than the total captured this year at the Arizona border. A crackdown at sea and tighter political asylum rules reduced the flow.

Asian smuggling kingpins are known as snakeheads; like killer snakes, they react with stealth and agility. Thus, changing border-crossing patterns reflect reconfigured tactics abroad as the flow persists. Today, mafias favor air routes and exploit favorable visa policies for Chinese travelers in countries including Ecuador, Honduras and Venezuela, which are hubs for their travel to Mexico, officials say. Many migrants report also stops in Cuba, officials say.

U.S. investigators have gathered intelligence about thousands of Chinese who have settled temporarily in Ecuador with the intention of being smuggled into the United States, according to a high-ranking federal official. “The smugglers are attuned to nuances in South American visa policies, and will adapt,” Allen said. Apprehensions of Chinese along the southwest boundary oscillate. Border-wide arrests hit 2,060 in the 2006 fiscal year, dipped to near 700 during the next two years, and then rose to 1,221 as of August, according to Border Patrol statistics.

The Patrol’s McAllen sector in South Texas, a high-volume corridor for non-Mexicans because of its relative proximity to Central America, led all sectors with at least 667 arrests of Chinese by August, officials say. But the Tucson area experienced the most dramatic proportionate surge. The convergence of drugs and illegal immigrants in the Sonora-Arizona area helps explain that, officials say. The dominant drug mafia in the region, the Sinaloa cartel, “saw an opportunity to get into Chinese smuggling,” said Mario Escalante, a Border Patrol spokesman.

The evolving alliance between traffickers of drugs and immigrants, once separate specialties, is complex. Investigators say that drug lords use their firepower to control turf and tax migrant smugglers for use of border corridors, known in Spanish as “plazas,” charging from $50,000 to $100,000 a week, officials say. “The drug trafficking organizations in the plazas control who smuggles, what they smuggle, where they smuggle,” said Allen, the ICE chief in Phoenix….

As in the past, the Chinese come almost exclusively from the province of Fujian. Another fixture of the trade: corruption speeds the passage of precious human cargo. In the 1990s, Mexican investigators broke up Chinese smuggling rings assisted by Mexican authorities.

And in May, two Mexican immigration police officers based at the Mexico City airport were arrested. Alerted in advance by smugglers, the two allegedly met Chinese travelers arriving on international flights. The officers allegedly gave the migrants fraudulent documents and sent them north to the border where the crossing continues, desperate but quiet.