MONTERREY, Mexico — Out of the desert scrub, the tycoons of Monterrey have erected an industrial powerhouse that is a beacon across Latin America.

Nestled against mountains near the border with Texas, Mexico's richest city is home to an array of steel, glass and banking industries that have earned it the nickname Sultan of the North. Its corporate ranks include the world's largest supplier of building materials and the largest beverage company in Latin America.

But with a speed that has surprised even astute industrialists, gangsters have brought the prosperous metropolis to its knees. The news in Monterrey grows darker by the day.

The Aug. 25 firebombing of a casino in broad daylight, leaving 52 people dead, certainly brought a global spotlight to the city of 4 million. But the wave of crime that has engulfed this industrial colossus is far broader and is pulling the city into a swirling spiral of violence.

It's now no longer unusual for mobsters to hang their victims from bridges for commuters to see on their way to and from work. The city's old quarter, once crowded with weekend revelers along its cobbled streets, is now a ghost town, plastered with "For Sale" signs. Gunmen roam in convoys in broad daylight hunting for vehicles to carjack.

"This used to be a first-class city. Not anymore," said Carlos Camino, a 32-year-old systems engineer, as he waited to report the theft of his silver Mazda SUV.

His wife, Daniela, was driving their 4-year-old daughter, Karen, to daycare at 7 a.m. a few days ago. Two blocks from their house, thugs in two vehicles blocked her car's path. One approached, pistol at the ready, and bashed on her window.

"He shouted, 'Get out of the car! Get out!'" Camino said. His wife grabbed their daughter and fled, arriving home in sobs, just one of 70 or so car owners that day to lose their vehicles in Monterrey, which has seen a tenfold increase in car thefts in a little over a year.

The criminal squeeze on Monterrey has dimmed a beacon for development for all of Latin America. The city's tycoons, feted as heroes, have built global giants like CEMEX (cement), FEMSA (beverages), Vitro (glass), ALFA (petrochemicals), Gruma (cornmeal and tortillas) and Banorte (financial services).

Residents are more likely to brag of ties to Dallas or Houston than to the rest of Mexico. At over $17,000, per capita income here is nearly double Mexico's average.

But the rise of crime gangs has shaken civic activists' confidence, even as they try to put on a brave face.

"Some people say, 'If Monterrey falls, Mexico will fall, too.' We prefer not to put it that way," said Miguel B. Trevino, head of the Civic Council of Nuevo Leon Institutions, a coalition of local community groups.

Trevino struggled, though, to articulate how his metropolis would deal with the underworld metastasis gnawing through its streets.

"We want to believe that the city has touched bottom," Trevino said.

Monterrey's industrial growth dates to the U.S. Civil War, when businessmen sent goods to the Confederacy. Within a few generations, tycoons founded Mexico's leading private university and built a city of modern highways, office parks and industrial zones.

The global supply chain began to loop through Monterrey, barely two hours drive from the U.S. border, and the city set its sights on loftier goals. It built a cluster of aerospace industries and began providing medical services aimed at wealthy visitors from elsewhere.