Mexico's Attorney General says security forces have arrested 74 people, including 17 police officers, in connection with the massacre of dozens of people in northern Mexico. Soldiers have uncovered 183 bodies during the last couple of weeks in mass graves in the town of San Fernando near Texas. It is one of the most gruesome finds so far in Mexico’s bloody war on drug cartels. The Attorney General declined to give more details about any possible motives for the massacre. Two bodies have been identified and returned to relatives while tests are being conducted on the rest for identification. The graves were found at a ranch where the Zetas drug gang allegedly killed 72 central and South American migrants last year. Authorities have freed 119 people held captive after two separate raids in the border city of Reynosa. Meanwhile, police said among those freed were six Chinese, 14 Guatemalans, two Hondurans, two Salvadorans and 27 Mexicans. A group rescued last week included a dozen Central Americans presumably kidnapped by the Gulf cartel. The Attorney General said the kidnappers intended to hold victims until their relatives outside Mexico paid up to $2,000 in ransom. Mass kidnappings have become common in northeast Mexico. Authorities believe the Zetas may use kidnapping as a means of recruitment.