3 men charged in killings of 2 Mexican federal agents in northern Mexico

3 arrested in killings of 2 Mexican federal agents

MEXICO CITY — Three men with ties to a drug cartel have been charged with the killings of two federal police officers in northern Mexico, authorities said Thursday.

The men, ages 20, 21 and 24, worked for the Zetas cartel, said Luis Cardenas Palomino, regional security chief of the federal police.

Police also seized two weapons and two grenades and are looking for more gunmen, he said.

Nuevo Leon state prosecutors said the officers had stopped a car for revision Wednesday when gunmen in several SUVs arrived at the scene and opened fire.

Prosecutors say a third federal officer was wounded in the attack in the town of Garcia.

Hours later, police found the bodies of a local traffic police officer and a trainee inside a car in the nearby town of Santiago. Prosecutors said they also found two automatic rifles, a handgun and a bulletproof vest.

More than 22,700 people have been killed in Mexico since President Felipe Calderon launched a military crackdown on drug cartels shortly after taking office in December 2006.

(This version CORRECTS the name of the regional security chief.) )