The police chief and all 38 police officers of a north-eastern Mexican town have quit following a series of drug cartel attacks, including the decapitation of two of their colleagues.
Soldiers, state and federal police had been deployed to patrol General Teran, a town along a drug-smuggling route to the US border, said Mayor Ramon Villagomez.
The police quit after the discovery of the mutilated bodies of two officers who had been kidnapped by gunmen two days earlier.
The killings followed three attacks on the police headquarters since December. Gunmen hurled grenades and sprayed the building with machine-gun fire.
Mr Villagomez said another police officer has been missing for weeks in the town of 14,500 people south-west of the industrial city of Monterrey.
Mass police resignations have been common in small towns in Mexico.
Municipal police complain they are outnumbered and outgunned by Mexico’s brutal drug cartels, who frequently stage bold attacks on security forces with semiautomatic assault rifles and grenades.
President Felipe Calderon has introduced a proposal in Congress to dissolve Mexico’s more than 2,000 municipal police forces. They would be replaced by a single force for each of Mexico’s 31 states.
Municipal police are generally underpaid and susceptible to corruption. Many have only an elementary school education. In some towns, police have protested that they lack bullets and flak jackets.
Mr Villagomez said General Teran’s officers earned around 9,200 pesos (£478) per month.