By MARION LLOYD
Copyright 2008 Houston Chronicle

MEXICO CITY — The U.S. State Department reissued a travel advisory for Mexico on Monday, warning Americans of increased drug-related violence and kidnappings, particularly in the embattled border region.

"Recent Mexican army and police force conflicts with heavily-armed narcotics cartels have escalated to levels equivalent to military small-unit combat and have included use of machine guns and fragmentation grenades," the alert reads.

It says Ciudad Juarez, Chihuahua and Tijuana are particularly dangerous.

U.S. officials justified the need to update the previous alert, issued in October 2007, to include details on the ratcheting up of the drug war over the past year. Mexican President Felipe Calderon has deployed thousands of troops to combat the narcotics cartels, which, after a brief retreat, are fighting back.

The alert "reflects the current reality in Mexico, including the increased violence on the U.S.-Mexico border," U.S. Ambassador Tony Garza said in printed comments.

More than 2,500 Mexicans were killed in gangland-style violence last year, and the death toll could exceed that this year, according to news reports. Police and soldiers increasingly count among the victims.

In addition, the alert said, "armed robberies and carjackings, apparently unconnected to the narcotics-related violence, have increased in Tijuana and Ciudad Juarez."

The alert stopped short of warning Americans not to visit Mexico, which receives more than 12 million American visitors a year. The Mexican government did not have an official comment on the alert, which was issued late in the day.