At least 31 PKK terrorists have been killed in ongoing security operations in Turkey's southeastern Hakkari province within the last 24 hours, Turkish military said Thursday.According to statements posted on the Turkish General Staff website, the military killed 15 PKK terrorists on Wednesday and another 16 members of the organization on Thursday in ongoing security operations in Hakkari province's Yüksekova district.Two Turkish soldiers were killed and another was slightly injured Wednesday in the same operations.Separately, 10 PKK terrorists surrendered to security forces in Turkey's southeastern Şırnak province Thursday, the army added.Meanwhile, a police officer was killed in clashes with terrorists in southeastern Diyarbakır province's Silvan district. The clashes took place as the police were carrying out an operation to fill in trenches dug by the organization's Youth Movement (YDG-H).A curfew was declared in three neighborhoods of the district on Tuesday. It is not yet clear when the curfew will be lifted.In a separate incident, the terrorists killed a soldier on Thursday in Diyarbakır's Dicle district and wounded another following clashes in the rural area. A curfew has been imposed in the region. Turkish army began its air-and-ground operations against PKK terrorist organization inside Turkey and northern Iraq in late July, as the PKK renewed its armed campaign against the Turkish state following a two-and-a-half year cease-fire. The PKK is considered as a terrorist organization by Turkey, the U.S. and the EU.