As Mexico’s drug war heats up, local police officers often find themselves outgunned by drug gangs, many of which have purchased combat arms at U.S. gun shops and shows, or – in some cases – stolen them from police stockpiles.

Now, however, Mexico’s governors are fighting back. As Mexico’s El Milenio reports, since 2009 the country’s Secretariat of National Defense (Secretaría de la Defensa Nacional – SEDENA) has received requests from at least nine state governments for hand grenades in order to give their local police forces an edge in the war on drugs.

The defense agency has already given hand grenades to police in several states, including Zacatecas, Guerrero, Coahuila and Yucatan. On the waiting list for the explosives are Guanajuato, Jalisco, and Veracruz, which are expected to arm some local police with grenades by the end of the year.

Hand grenades are not the only comparative advantage that state governments are seeking. As the Associated Press reported in 2008, governors are also trying to get higher caliber rifles for their security forces, as well as more ammunition. Their adversaries, foot soldiers of Mexico’s cartels, are often equipped with .50 caliber sniper rifles, AK-47 variants, and body armor.

Although Mexican Federal Police and state police in Chihuahua, Jalisco, Chiapas and Guerrero use AR-15 and G36 assault rifles, most municipal and state police in Mexico are armed with shotguns or .38 caliber pistols, which hardly compete with the heavy arsenals of drug gangs.

As more states seek to beef up their security arms stockpiles, however, there is a risk that some of these weapons will actually end up in the hands of the cartels they’re meant to fight. Since the beginning of Mexico’s war on organized crime, dozens of police weapons have been “lost,” likely ending up in the country’s black market for arms. According to El Milenio, 156 handguns and 97 rifles have gone missing from state police arsenals since 2009. The largest number of lost weapons is in Chihuahua, where a total of 36 pistols and 57 high-powered rifles have simply vanished in the past two years.

Ultimately, the Mexican military is a fairly insignificant source of weapons for the cartels. As InSight has described in its GunRunners report, the majority of these weapons come from the United States. In the four years that Felipe Calderon has been president of Mexico, his government has seized more than 93,000 weapons, close to 90 percent of which come from gun stores in U.S. border states like Texas, Arizona and New Mexico.

The most popular of these weapons is a knockoff of the AK-47, the Romanian-made WASR-10. These semi-automatic rifles are readily available in many American gun stores, despite U.S. restrictions on the importation of assault weapons. In the end, the biggest factor in keeping these rifles out of the hands of Mexico’s drug gangs is limited oversight that government agencies have over arms dealers. Unless something is done to control access to assault weapons in many of the 6,700 gun stores along the southern border, Mexican police will continue to face cartel gunmen armed to the teeth.