AYUTLA DE LOS LIBRES, Mexico (AP) — Fed up with police corruption and drug gang violence, a number of communities in the southern Mexico state of Guerrero and neighboring areas have formed citizen police groups.

Effectively vigilante outfits with no allegiance — and often outright hostility — to elected authorities, they are grassroots attempts by locals to rein in lawlessness in some of the areas most wracked by killings, kidnappings, extortion and other malfeasance.

Such forces have multiplied in recent years as Guerrero has become more violent. The state saw 2,318 homicides last year as criminal gangs battled for territory or killed to intimidate victims.

For these citizen cops, being on duty can mean manning an impromptu roadblock to search vehicles for contraband, monitoring bars for nefarious activities or watching over rudimentary police stations complete with jail cells.

Patrolling on foot or in the back of a pickup truck, they are often armed with just rifles — a far cry from the high-caliber weapons used by Mexico's drug cartels, police and military.

It can be a deadly job. Daniel Julio Julio, a 22-year-old member of one militia, was ambushed and killed in the Guerrero village of Huamuchapa.

Civilians die at the vigilantes' hands as well. Alexis Estrada, Asencio, a 17-year-old bull-riding enthusiast, was allegedly killed by members of the local vigilante force in January in La Concepcion along with five other people. The vigilantes were allied with groups trying to halt a large dam project backed by the government.

The groups sometimes clash with one another as organized crime groups try to coopt and divide them.