Bodies of 11 men and one woman were found dumped in an empty lot next to a Tijuana elementary school this morning

The bodies of 11 men and one woman were found dumped in an empty lot next to a Tijuana elementary school this morning, an hour before children were scheduled to arrive.City officials suspended classes after finding the victims, most of whom had been bound and tortured. Some were only partially clothed, said Tijuana police spokeswoman Prisna Perez.Minutes after the grisly discovery, four other bodies were found in another empty lot in Tijuana, and two other bodies were discovered late Sunday in a lot next to a factory. Police have not determined whether the 18 killings were linked, or whether the city's drug gangs are responsible, Perez said.
Tijuana is among the cities hardest hit by violence as Mexico's drug cartels battle for lucrative smuggling routes past the border to supply illegal drug users in the United States.Nearly two years ago, President Felipe Calderon launched a nationwide battle to take back territory controlled by some of the world's most powerful drug gangs, and the cartels have responded with unprecedented violence.In April, rival gang members killed each other all over Tijuana in simultaneous attacks that left at least 13 dead. A shootout in January forced the evacuation of a Tijuana preschool, with live television footage showing children fleeing ricocheting bullets.The violence has battered the border city's once-boisterous tourist economy, silencing discos and shops.