The Mexican government is acknowledging that U.S. intelligence agents operate in Mexican territory to help combat drug cartels, but details are sketchy about the extent of the collaboration.
Thus far, the government has refused to discuss the latest report that intelligence agents have been posted to a base in northern Mexico and have helped in interrogations, wiretaps and running informant networks.
The participation of U.S. agents and the designation of a new U.S. ambassador, Anthony Wayne, whose last posting was Afghanistan, has raised concerns that America may view Mexico as an Afghan-style battleground.
Mexico has already acknowledged it allows U.S. drones to conduct non-piloted surveillance flights over Mexican territory, though it says it "controls" the flights; a Mexican official is present in the drones' control room.
"In recent months, Washington's growing military, political, intelligence and police interference has been documented in many ways, as has the Mexican government's acceptance of it," the newspaper La Jornada wrote in an editorial Monday.
The New York Times reported over the weekend that CIA agents and former U.S. military personnel are working at a Mexican military base, and that officials have weighed the possibility of sending private military contractors. The use of such contractors in Iraq and Afghanistan was marred by scandals.
The office of Mexico's federal security spokesman, Alejandro Poire, said in a statement late Sunday that U.S. agents do participate in analysis and exchange of information, but don't carry weapons or participate in operations like raids, or arrests.
But the statement that the government won't discuss specifics of the agents' role "for national security reasons."
The statement said the U.S. cooperation "is carried out with unrestricted respect for Mexican law."
The Associated Press has been able to identify several hundred U.S. agents working in Mexico.
According to that tally, the Drug Enforcement Administration has more than 60 agents in Mexico. There are 40 Immigration and Customs Enforcement agents, 20 Marshal Service deputies, 18 Alcohol, Tobacco, Firearms and Explosives agents, and dozens more working for the FBI, Citizen and Immigration Service, Customs and Border Protection, Secret Service, Coast Guard and Transportation Safety Agency.
The U.S. has committed to giving Mexico $1.5 billion in anti-drug aid since 2008 under the Merida Initiative.
According to official figures, at least 35,000 people have been killed in drug violence in Mexico since late 2006, when President Felipe Calderón launched his crackdown on organized crime. Other sources, including local media, say the number is closer to 40,000. The federal government has not released an update of its numbers since December.
Based on reporting by the Associated Press.