MEXICO CITY - More than 250 federal police agents surrounded the offices of the Oaxaca state police force and seized its weapons Friday to determine whether any were used in shootings during six months of demonstrations in Oaxaca City, federal authorities said.
At least nine people have been killed in a conflict that dates back to May. Most were protesters who were shot by gangs of armed men, and activists blame local police for many of those shootings.
Around 200 people have been arrested in recent weeks in connection with sometimes violent demonstrations in which protesters took control of Oaxaca City, battled police, and torched vehicles and buildings.
On Friday, human rights groups and families of those detainees asked U.N officials to intervene, claiming some prisoners had been beaten, tortured and sexually abused.
They also argue there is no evidence that most of the prisoners committed any crimes and asked for U.N. officials to visit the prisons and pressure the Mexican government to guarantee the detainees their rights.
Federal and state officials deny the prisoners have been mistreated and say they are just upholding the law.
Protesters have demanded the resignation of Oaxaca Gov. Ulises Ruiz, whom they accuse of thuggery and corruption. Ruiz denies those accusations. In October, more that 4,000 federal police swept into Oaxaca and pushed the protesters out of the city.
The wave of arrests has taken the sting out of the protests, which scared tourists away from the city and shattered the local economy.
During Friday's operation, federal agents also detained five employees of the Oaxaca state justice department who were using stolen automobiles, federal authorities said in a statement. In Mexico, members of police forces sometimes use recovered stolen cars until the owners are located.
The weapons seized Friday apparently will be returned if the state police are found to have the proper registration and permit documentation for them.
Members of the special federal police group 'GOPES' stand guard outside a police station in Oaxaca City December 8, 2006. Mexican federal police stormed the state attorney general's offices in the conflict-torn city of Oaxaca on Friday, seizing agents' guns to check if they were used in the killings of more than a dozen people.