| MONTERREY, Mexico
MONTERREY, Mexico When criminals beat small-town mayor Gustavo Sanchez to death with rocks this week, Mexicans were horrified but no longer shocked by the latest attack on a local leader in the country's vicious drugs war.
The slaying of Sanchez, which police blamed on drug hitmen in marijuana-producing Michoacan state, underscored the vulnerability of elected officials as President Felipe Calderon intensifies his fight against powerful drug cartels.
Last week, suspected drug hitmen shot and killed the mayor of a rural town outside Monterrey, the northern business city with close U.S. ties. Another shooting hours later left a mayor-elect in northern Chihuahua state critically wounded.
Drug hitmen have killed at least 17 mayors across Mexico since early 2008, according to media tallies. Five of those have died in the past six weeks as gangs seek to control towns along key smuggling routes into the United States.
"They've threatened to kill me twice. They wanted me out of the way to have total control," said Mauricio Fernandez, the mayor of San Pedro Garza Garcia near the Texas border, the country's richest municipality that is part of Monterrey.
The attacks on elected officials add a new element of fear to the fight against cartels in Mexico, where drug violence has killed over 29,000 people since Calderon launched his drug offensive when he took office in late 2006.
Cartels "have reached a point where they are prepared to confront the authorities in this country in a way that threatens the wider population," U.S. Ambassador to Mexico Carlos Pascual told reporters last week.
Motives for the killings are not always clear. Police at times suspect murdered officials have upset drug gangs or were killed by hitmen who accused them of ties to rival cartels.
Calderon, a conservative, vowed to "redouble our fight against these criminals" after the killing last week of the second mayor murdered near Monterrey since mid-August.
The body of Prisciliano Rodriguez, mayor of the town of Doctor Gonzalez near Monterrey, was left on a rural road, his white Stetson hat sitting nearby, after gunmen shot him on Thursday evening.
Officials blame the surge in violence around Monterrey and in neighboring Tamaulipas state on the rivalry between the Gulf cartel and its former armed wing, the Zetas.
Many residents in Monterrey and surrounding Nuevo Leon state, once an oasis of calm and prosperity, are terrified.
"Doctor Gonzalez is a no-man's land. It was just a matter of time before this happened," said a local resident who declined to give his name. "No one goes out at night."
This week, a cartoon in El Diario newspaper in Ciudad Juarez, the violent city across from El Paso, Texas, showed a mayor with a giant bull's eye on his cowboy hat.
WELL PAID BUT VULNERABLE
Winning a spot as mayor can be the start of a long, lucrative political career in Mexico, and many mayors have relatively high salaries, even those running small towns.
But mayors are also reliant on ill-equipped and often corrupt local police for protection, making them easy targets for drug gangs who have infiltrated police forces across Mexico.
The mayor of the town of Santiago near Monterrey was abducted last month by his own police and handed over to the Zetas to be killed, preliminary state investigations show.
Some among a slew of new mayors who take office for a three-year term in October already received threats from cartels during their election campaigns.
The government says it is doing everything it can to keep public officials safe. "We're working hard to identify those who may be at greater risk," Mexican national security spokesman Alejandro Poire told reporters on Tuesday.
Few mayors are as fortunate as Fernandez, who was tipped off by U.S. authorities about a murder plot last year and who has the support of some of Mexico's biggest companies in his plan to spend $50 million on reforming his police force.
Fernandez is known across Mexico for creating a paramilitary squad to go after kidnappers shortly after taking office -- though he says it has since been disbanded.
Officials in Chihuahua, Mexico's most violent drug war state, feel extremely vulnerable despite the army presence.
"I don't know how the government is going to look after the security of the new mayors near Ciudad Juarez. There is so much fear," said Victor Quintana, a leftist lawmaker in Chihuahua.
(Additional reporting by Alexandria Sage in Mexico City and Julian Cardona in Ciudad Juarez; editing by Missy Ryan and Kieran Murray)