Army troops captured 10 suspected Gulf cartel gunmen who were wanted in connection with an attack on a bar that left 20 people dead in Monterrey, the capital of the northern Mexican state of Nuevo Leon, a military spokesman said.

"The people detained said they belonged to the Gulf cartel criminal organization and participated in the attack on the Sabino Gordo bar in which 20 people lost their lives on July 8 of this year," a military officer who took part in the operation told Efe.

The suspects also confessed to the killings of four other people at the Cafe Iguana in May and a series of other crimes.

The suspects told the army that they strung up some of their victims from pedestrian bridges in Monterrey, the military spokesman said.

The suspects said their job was "to find and murder individuals who belonged to rival criminal organizations, traffic drugs and steal vehicles in Monterrey," the military spokesman said.

The suspected gunmen were arrested on Dec. 2 at a house in the southern section of Monterrey.

Soldiers seized 10 rifles, a fragmentation grenade, five vehicles, drugs and the house in the operation.

Monterrey, Mexico's most important industrial city, and its suburbs have been battered by a wave of drug-related violence since March 2010, when three rival cartels reportedly went to war with Los Zetas, considered the country's most violent criminal organization.

Los Zetas has been battling an alliance of the Gulf, Sinaloa and La Familia drug cartels, known as the Nueva Federacion, for control of the Monterrey metropolitan area and smuggling routes into the United States.

Heriberto Lazcano Lazcano, known as "El Lazca," deserted from the Mexican army in 1999 and formed Los Zetas with three other soldiers, all members of an elite special operations unit, becoming the armed wing of the Gulf drug cartel.

After several years on the payroll of the Gulf cartel, Los Zetas, considered Mexico's most violent criminal organization, went into the drug business on their own account and now control several lucrative territories.

A total of 267 murders were registered in the industrial city in 2009, with the figure rising to 828 in 2010 and nearly 2,000 so far this year, according to official figures.

A total of 15,270 people died in drug-related violence in Mexico last year, and more than 45,000 people have died since President Felipe Calderon declared war on the country's cartels shortly after taking office in December 2006. EFE