The latest installment in a decadeslong battle between a Kurdish military group and the Turkish government claimed seven more lives Sunday, Agence France-Presse reported. Three police officers, three Kurdish rebels and a 12-year-old civilian boy lost their lives in separate parts of the country.

A battle in Silopi claimed the lives of three Kurdish fighters and one Turkish police officer, while two more police officers were shot dead in Diyarbakir, a regional capital in the southeast. The boy died after stepping on a landmine that local officials say members of the Kurdistan Workers Party, or PKK, planted.

Earlier this month, Murat Karayilan, who leads the PKK’s Iraq-based forces, said the Turkish government would pay a “very heavy price” for its decision to launch a series of airstrikes against PKK targets. Since then, attacks on Turkish fighters have led to some 60 deaths in recent weeks. Turkey's President Recep Tayyip Erdogan has countered with his own strong words, saying his military forces will continue to fight the PKK until "not one single terrorist" remains. 

The battle between Turkish authorities and the PKK stretches back more than 30 years, to when the PKK launched a violent campaign against the Turkish government, demanding Kurdish autonomy within Turkey, in 1984. Since then, fighting between the two sides has claimed more than 40,000 lives.

A ceasefire brokered in 2013 provided a respite, but a suicide bombing by inside Turkey -- by fighters from the Islamic State group, and which PKK forces accused Turkish authorities of being involved in -- sparked a new round of violence. Days after the July 20 bombing, PKK forces claimed responsibility for suicide attacks in southeastern Turkey, which borders Syria.

A number of governments, including the United States, European Union and Turkey, consider the PKK a terrorist organization.