Security forces were tipped off about suspicious activity at a ranch in Quiche, in the central highlands, by residents who said men in ski masks were asking villagers to join their ranks, police chief Marlene Blanco said at a news conference.

Two commanders of the Zetas, the armed wing of Mexico's Gulf cartel, and 37 recruits fled the camp before the police and army arrived, leaving behind 500 grenades, six rifles and hundreds of rounds of ammunition, Blanco said.

The spiraling violence of Mexico's drug war, where rival cartels have resorted to savage tactics in their struggle for territory, killed more than 6,200 people last year and has stoked increasing concern from both ordinary Mexicans and the country's neighbors.

"They wanted to recruit young men. They offered training in the use of certain weapons and said they had jobs," Blanco said.

Guatemalan authorities, helped by personnel from the U.S. Drug Enforcement Administration, also found an illegal airstrip, an obstacle course and equipment for practicing shooting at moving targets.

"We are facing a war against drug trafficking and you can see what kind of weapons they have waiting for us," Blanco said.

Mexican President Felipe Calderon has deployed tens of thousands of soldiers in a bid to crack down on the violence.

Police believe a series of attacks on buses in Guatemala City in the past week were orchestrated by the Zetas to distract attention from the border where they had been shipping illegal arms and drugs into and out of the country.