MEXICO CITY — At least 20 people were killed — even the hot dog vendor outside — when armed men sprayed gunfire on a bar in Monterrey, Mexico, late Friday, the latest sign of the business hub’s slide into violence in the past year and one of three slaughters over the weekend.
In other parts of Mexico, 11 bodies with gunshot wounds were found near a well on the outskirts of Mexico City, and 10 decapitated heads were found in Torreon, 500 miles north of the capital.
The weekend bloodshed prompted Alejandro Poire, the federal government’s security spokesman, to defend its crackdown on drug cartels and organized crime and blame the violence on a fight to the death among the groups.
Since President Felipe Calderón began an assault against criminal groups in 2006, more than 35,000 people have died, the government has said, though newspapers here say the toll is closer to 40,000. Polls have shown the public growing increasingly worried that the government has been unable to stem the violence.
“The violence is the product of this criminal rivalry, characterized by mistrust, vengeance, the intent to control all illegal activities of a community and profit not just from that activity but also the possible control of drug shipments to the United States,” Mr. Poire said at a news conference.
Nevertheless, the wave of violence demonstrated the staying power of groups the government has asserted it was making progress defeating by killing or arresting leading members. The Zetas in particular are considered among the more ruthless and blamed for mass carnage here and in Central America.
Although the authorities have not identified suspects in any of the killings, Mr. Poire said they occurred in the backdrop of cartel fights.
Outside Mexico City in surrounding Mexico State, the Zetas and Knights Templar are battling, he said. The Knights Templar emerged as an offshoot of La Familia, just as the government was claiming success in weakening that group, which has carried out mayhem in Mr. Calderón’s home state, Michoacan.
In Torreon, he said, the Zetas are fighting the Sinaloa cartel, headed by Joaquin Guzman, known as “El Chapo” and the most wanted man in Mexico.
The Monterrey attack, where the Zetas and Gulf cartel are trying to extinguish each other, occurred in a bar that had a reputation as a hang out for drug users, reported El Norte of Monterrey, which called it one of the worst massacres in Nuevo Leon State to date.
“They killed the hot dog vendor, someone known as “Mena,” and the doorman outside, and then they went in with their guns shooting,” the newspaper quoted an unnamed witness.
The violence in Monterrey, once a tranquil and prosperous business and industrial hub, has led business and civic leaders to plead for more help from the government. It has sent military and federal police forces there, but the attacks continue.
“The violence will diminish as we accelerate our capacity to debilitate the gangs that produce it,” Mr. Poire said.