The people of Villanueva said they’d had enough. Men in cowboy hats, women with hand-scrawled signs, children on bikes -- they gathered outside town and blocked the main interstate highway.

“If you can’t do it, quit!” they told their police force. They demanded that the army take over.

The army rolled into this town in Zacatecas state last month and ordered the police to stand down and surrender their weapons. They did.

Things only got worse. A few days later, Police Chief Romulo Madrid, a former military man said to be eager to cooperate with the army, was shot and killed outside his house at 10:30 on a bright morning. The mayor’s chauffeur, a first cousin, was arrested in the shooting.

Five days later, gunmen working for a drug gang ambushed an army patrol. One soldier and four assailants were killed. Among the attackers captured was a police officer. Sources close to the military point to evidence that elements of the police force set up the army patrol.

For Mexicans to call on the armed forces, whose human rights record has been dubious at best, testifies to the firm conviction that the state and its civilian authorities, including the police, no longer protect them from the gang warfare of narcotics traffickers.

Shootings, kidnappings, extortion and threats have shattered the relative peace of Zacatecas, a central mountainous state that sends a greater proportion of its people as migrants to the United States than almost any other.

The unrest has disrupted immigration patterns, brought the local economy to its knees, destroyed small-town life and now threatens the upcoming planting season in an area that relies heavily on agriculture.

“They are impotent,” Lorenzo Marquez, a merchant, said of the authorities. From the market stall where he sells cheese, sausage and jalapeno peppers, he has watched too many incidents of thugs hauling people away at gunpoint in broad daylight. “And we the people are even more impotent.”

‘Criminal groups’

Carlos Pinto, the powerful interior minister for Zacatecas, acknowledged that “criminal groups, every day more violent, are challenging the state.”

“Our institutions are not proportionate to the needs,” he said. “This problem grabbed us without our police being ready or properly equipped.”

Rodolfo Garcia Zamora, a researcher at the Autonomous University of Zacatecas, says that immigration may increase from the state, and that citizens left here could take the law into their own hands.

“The threat is of social and political decomposition in Zacatecas, and in the nation, in which the authorities remain subordinated and violence is the norm,” he said. “The situation has overtaken the government and its institutions.”

Zacatecas has long been a corridor for smuggling routes from central Mexico northward, with the trafficking gangs from the Pacific state of Sinaloa in control of most activity. Then, several years ago, violence surged as members of the so-called Gulf cartel and their hired guns, the Zetas, began moving in to challenge their Sinaloa rivals.

Criminal opportunists move in as well, taking advantage of the fear and collapse of law and order.

The last straw

For the people of Villanueva, the last straw was the kidnapping last month of Roberto Garcia Cardenas, a retired professor in his 60s nicknamed El Pollero, the Chicken Man, for his part-time job selling chickens in the market. Garcia was also a money lender, a business that won him many properties, and many enemies.

Garcia’s family was able to raise the 600,000 pesos (about $40,000) his kidnappers demanded. But when his children arrived to pay the ransom, the kidnappers seized them: a 24-year-old daughter who had given birth just a few weeks earlier, and a half-blind 17-year-old son. They sent Garcia out to gather a new ransom, this time more than 3 million pesos (about $200,000). “They threatened me and beat me,” Garcia said of his kidnappers.

Garcia desperately drove through the streets of Villanueva, with megaphones on the roof of his car, offering to forgive the high interest he was charging if borrowers would pay the principal they owed. He tried to hawk some of his properties.

Eventually the children were freed in an operation that remains mysterious. The family, like most that have endured a similar ordeal, fled Zacatecas.

The Garcia story was only the most chilling in a long string of kidnappings. State prosecutor Ambrosio Romero said he registered 30 cases last year and six in January but acknowledged that far more cases are not reported. The perpetrators obtain information on their victims by surfing the Internet and often contact families in the U.S. to wire the ransom money. In some cases, kidnappers showed up with a public notary so the victim could sign over deeds to his properties.

Place of migration

For the last century or so, Zacatecas has sent tens of thousands of migrants to the United States to work, legally and illegally. They in turn send money back (about 10% of the state’s GDP last year), and many eventually return to set up businesses, build homes (one story each year) and deal in property. Many ultimately retire in Zacatecas. All of that is changing.

For-sale signs are popping up everywhere; businesses such as restaurants, clothing stores and mechanic workshops are being shuttered. Many Zacatecas residents who live abroad have stopped returning. The horse tracks and dance halls that returning migrants favored have been abandoned. A public notary said her work validating business and property sales has fallen 80%. Antonio de la Torre del Rio, the mayor of Villanueva, says the construction company he owns, which was selling more than 150 tons of poured concrete a week, now doesn’t sell that much in a month. According to one academic study, 75% of the towns in Zacatecas are shrinking in population.

Villanueva, with 32,000 people, was famous for musicians who congregate in the central plaza to be hired, mostly by returning migrants. But now the musicians -- norteños with their trumpets, black-suited mariachis, and the native-son tamboreros with their huge drums -- all stand around, idle and largely silent.

Jose Guardado slumped in a corner of Villanueva’s leafy town square, his drum doubling as a billboard for his business. Guardado regrets his decision to move back to Villanueva after living in Washington state for 15 years; his brother Emiterio is already making plans to return to Chicago.

“People aren’t coming,” he said. “They’re afraid of getting kidnapped, robbed, killed. The police are no help. The police and the bad guys, they’re the same band.”

Patronage vehicles

Mistrust of the police runs deep here and throughout Mexico. Local forces are seen as corrupt and infiltrated by drug gangs. But they also are traditional vehicles for patronage, and small-town mayors and state governors are usually loath to lose control of them.

Villanueva Mayor De la Torre initially accepted his people’s clamor to hand security tasks over to the army. But he quickly changed his mind. He asked for his police to be reinstated, even though almost every member of the police force had flunked a test, administered by the army, to rate their qualifications and honesty.

De la Torre also defended his chauffeur and first cousin, arrested in the shooting of Madrid, the police chief.

Madrid was gunned down Feb. 2 as he stepped from his home. The chauffeur, Antonio de la Torre Quiroz, was arrested as a material witness and remains under investigation. Two senior government sources close to the case said they believed the man served as a lure to get Madrid out of the house. The sources spoke on condition of anonymity because details of the investigation are not public.

Mayor De la Torre acknowledged that violence and fear have reached unprecedented levels. “Someone is kidnapped, and everyone says, ‘Who’s next?’ ” he said. “We can’t continue this way. The town is dying.”

If citizens don’t trust the police, neither, it appears, does the military. An army patrol was ambushed Feb. 7 in the Zacatecas town of Fresnillo by drug-gang gunmen who attacked the soldiers from at least two flanks, killing a sergeant and leaving a colonel badly wounded. Among the attackers killed was a senior regional commander of the Zetas, and among those captured was a police officer.

Sources close to the military say that two police units meant to accompany the army patrol inexplicably missed a final turnoff along the route and were not present when the gunfire erupted.

wilkinson@latimes.com