Armed men raided an elementary school in Agusan del Sur province in Mindanao Thursday and took 55 children and teachers hostage, authorities said. The kidnappings come just after a massacre in a nearby province in which 57 people were killed, raising tensions ahead of presidential elections next year. The hostages were being held in a mountainous area near Prosperidad town in Agusan del Sur province, officials said. The 15 gunmen later demanded that a raft of charges against them, including murder, be dropped, police said. The gunmen had abducted 75 people but later freed 18 of the victims, including 17 children, while two others escaped, said Chief Inspector Marco Archinue, police chief of Prosperidad town. Chief Superintendent Lino Calingasan, police director in the region, said the incident started when a group of armed men engaged in indiscriminate firing in La Purisima village in Prosperidad at around 8 A.M. Thursday. When police and soldiers responded, the gunmen proceeded to Sitio Maitum in Baranggay San Martin and seize the schoolchildren and teachers as well as other civilians from the Maitum Elementary School, Calingasan said. He said the gunmen were members of an organized-crime gang called Perez Group led by a certain Ondo Perez, who is reportedly a former member of a militia group Cafgu. Archinue said they had been hunting down the Perez group for its involvement in criminal activities in the province. “This group is engaged in criminal activities like robbery, homicide. We have been looking for them to serve the arrest warrants until this incident happened,” he added. Authorities described the gunmen as bandits who could have seized hostages because they were being boxed in by police.