Gunmen seized and killed six people, then got into a rolling shootout with Mexican soldiers Tuesday in a burst of violence that left at least 21 dead in the northern state of Chihuahua, officials said.
The scale of bloodletting was remarkable even for Chihuahua, the deadliest spot in Mexico as a year-old turf war has raged in the state between rival drug-trafficking groups.
Chihuahua, across the border from Texas and New Mexico, registered 2,000 drug- related killings last year, according to Mexican news media counts, and has logged more than 200 since Jan. 1.
Tuesday's incident began in the town of Villa Ahumada, which sits along a key highway route for smugglers 80 miles south of the violence-torn border city of Ciudad Juarez.
The region has been at the center of the war between Juarez-based traffickers and rivals from the northwestern state of Sinaloa. In May, dozens of attackers stormed Villa Ahumada, killing the police chief, two officers and three civilians. They also reportedly hauled off 10 other people.
On Tuesday, authorities said, the attackers kidnapped nine people and took them to a ranch, where they killed six of the captives before fleeing in two groups.
Mexican troops, who have led the government's crackdown on drug traffickers, caught up with seven of the gunmen and killed them during a shootout, said Enrique Torres, spokesman for joint military-police operations in Chihuahua. A soldier died and a second was wounded.
The remaining seven gunmen were killed later during separate clashes with soldiers who gave chase by land and helicopter. Three kidnapping victims were freed, Torres said.
President Felipe Calderon has deployed 45,000 troops across Mexico as part of a 2-year-old offensive against organized crime. The crackdown has exacerbated violent rivalries between big drug-smuggling organizations and contributed to a record number of killings.
Calderon told a Mexican newspaper Monday that more than 6,000 people died in the violence across Mexico last year. He said 90% of the dead were linked to criminal activities.
Tuesday's incident came as Mexican officials defended the use of the military in the drug war. Interior Minister Fernando Gomez Mont was quoted in Mexican news reports as saying the army's role was temporary and designed to give federal and local law enforcement officials time to clean up and improve police forces.