Gunmen opened fire and tossed a grenade at a crowded taco stand in the central Mexican city of Uruapan on Thursday, causing cooking gas tanks to explode and killing a police officer and a 15-year-old boy.
A spokesman for the state prosecutor's office in Michoacan state said the policeman was shot while eating with a fellow officer.
Before fleeing, the assailants shot two tanks of cooking gas that exploded, burning the teenage taco stand worker to death, the spokesman said on condition of anonymity because his office does not allow him to give his name. Four other people were injured.
Investigators said the attack apparently targeted the two officers.
Plagued by drug violence
Uruapan has been plagued by drug violence. The city's mayor was among 10 Michoacan mayors detained by federal officials last month for alleged drug ties. In 2006, suspected La Familia cartel members dumped five human heads on a bar dance floor in the city.
Drug gangs have been staging increasingly bold attacks since Calderon launched a national crackdown on cartels in 2006 by sending troops to Michoacan, his home state. More than 10,800 people have died in drug violence in Mexico since.
Also on Thursday, armed men barged into a motel room and killed five people in their beds in Ciudad Juarez, across the border from El Paso, Texas, said Victor Valencia de los Santos, public safety secretary for Chihuahua state. A sixth person was wounded.
Two other people were killed during a car chase and shootout between armed men in downtown Juarez, said Enrique Torres, a spokesman for the joint military and federal police operation responsible for security in the city. Both people killed were gunmen.
The federal Attorney General's Office, meanwhile, offered a 10 million peso ($737,000) reward for information on the whereabouts of Francisco Serrano, the customs administrator for the Gulf coast state of Veracruz believed to have been kidnapped this month.
Serrano recently launched a new system to check shipping containers at Veracruz, one of Mexico's most important ports and the scene of increasing drug violence.
Mexico's president vowed not to allow attacks on government and police derail the fight against drug trafficking.
"Wherever they attack our personnel, we will make it difficult for anyone to carry out their criminal activities," Calderon said during a speech in Veracruz.
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