Before an international incident that involved Turkey shooting down a Russian fighter jet Tuesday morning, which purportedly violated Turkish airspace several times, Ankara’s forces were also engaged in attacks against Kurdish revolutionary forces in the southeast of the country.

Turkish fighter jets fired upon several PKK (Kurdistan Workers’ Party) targets in the country’s southeast, the NATO-member military announced. The warplanes hit PKK shelters and supply centers in the Demdinli district of Hakkari province, near Turkey’s border region with Iraq and Iran.

Some 13 shelters used by PKK forces were destroyed during operations, the military said in a statement, adding that two PKK members were captured during the operations.

Five Kurdish revolutionary fighters were killed in the Turkish air offense, the Turkish military said.

Ankara’s offensive came after PKK militants carried out an attack on a deployment of Turkish forces in Diyarbakir, killing three and injuring seven soldiers. They used mines and automatic weapons in a series of attacks that racked up the casualty count.

Turkish officials in the Cizre district in the southeast of the country have declared a curfew due to continuing threats from the PKK. The curfew is set to start at 4:00 P.M. local time, the local governor announced.

The curfew was announced after a civilian working for the government as a security guard was executed by a PKK militant with an automatic weapon. Another man was injured as the Kurdish militants continued to fire upon his location, which was located at a local police headquarters.

According to AINA news, PKK militias have infiltrated eight Assyrian villages in northern Iraq. On Monday, they took over the villages of Hezani, Belmand, Khalilane, Zoly, Kashkawa, Meroke, Rabatke, and Upper Hezani, according to the report. And one of the homes taken over belongs to the leader of the Dwekh Nawsha, an Assyrian Christian fighting force.

The villages remain occupied into Tuesday, the Assyrian news agency reported.

AINA reports that villagers remain fearful that Turkey will conduct bombing raids on the village, leaving the locals with serious safety concerns.

The Russian government has long had close relationships with multiple Kurdish factions, including the Kurdistan Regional Government of Iraq (KRG), with which Turkey also maintains friendly relations, and the People’s Democratic Union (PYD) in Syria, which Turkey does not distinguish as separate from the PKK and considers a terrorist organization. Russian officials have issued statements decrying the designation of the PKK as a terrorist organization. The PKK has shown signs of disapproval of the Russian government’s approach to the fight against the Islamic State in Syria, however, with one PKK leader accusing Russia of “stealing a role” in the matter without properly cooperating with Kurdish fighters.