Nuevo Laredo’s new police chief was on the job nine hours before he was shot dozens of times and killed.

The dramatic murder of the top law enforcement officer in the increasingly violent Mexican border town, just across the river from Laredo, Texas, provided another stark illustration of the way the drug cartels are vying for power with law enforcement authorities.

Alejandro Dominguez, a businessman who once worked at the federal attorney-general’s office, was sworn in Wednesday afternoon, saying he wasn’t afraid of anything.

With many top police officials being ambushed and killed in the town recently, Mexican President Vicente Fox sent in soldiers to try to keep the peace.

“I don’t owe anybody anything,” said Dominguez. “My duty is to the citizenry.”

He was the nephew of former Attorney General Javier Coello Trejo.

“I think those who should be afraid are those who have been compromised,” he said hours before being killed.

After dark, a group of assailants opened fire on Dominguez as he was climbing into his Ford Lobo outside the city’s National Business Chamber, which he leads.

“We’ve recovered 35 to 40 casings from an AR-15 assault rifle,” state police director Fernando Vallejo said.

A witness told authorities Dominguez was targeted by a group of men who arrived at the scene of the shooting in three dark-colored Chevy Suburbans.

Since the beginning of the year, ambush-style shootings have claimed the lives of seven police commanders in Nuevo Laredo, including Dominguez.

Nuevo Laredo has been the front line of a turf battle between Mexico’s two largest drug gangs, the Gulf and Juarez cartels.

The position of police chief stood vacant for weeks after Jose Valdez left to take another municipal position. The city had a hard time finding applicants who weren’t afraid to take the job.

In all, shootings have claimed the lives of 61 people this year in Nuevo Laredo.

The U.S. government has issued a warning to tourists traveling to the border, which has seen a rise in drug violence amid a turf war between the country’s two main drug cartels.

In addition, U.S.-trained Mexican commandos recruited to fight drug smugglers have turned to protect them. The Zetas are heavily armed and perform paramilitary functions on behalf of the drug dealers. They are responsible for hundreds of murders along the border, say authorities.

Also on Wednesday, seven gunmen wearing ski masks entered a hospital in a northern Mexican state capital and killed a federal agent who was recovering there from gunshot wounds, investigators said.

The assailants, who also killed two men accompanying the agent, arrived at the Clinica del Centro hospital in Chihuahua City, just after 1 a.m.

After subduing security guards and covering surveillance cameras, the group moved into the room of federal agent Victor Estrada, said Rene Medrano, a spokesman for Chihuahua state attorney general’s office.

A former member of the federal judicial police force, Estrada was an 11-year veteran of the Federal Agency of Investigation who was suspended for vague investigative violations and reinstated in early March at the order of a Chihuahua judge, federal authorities said.

Previous stories:

The threat from Mexico

‘It’s a war’ along Mexican border

Mexican commandos seek control of border

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