Turkey, ISIL and the PKK

The move poses a new threat to negotiations between the government and the Kurdish militant group, which have become increasingly strained in recent weeks in the face of Turkey’s refusal to help rout jihadist militants across its border in Syria, where Kurds face the risk of a massacre by Islamic State.

Monday’s attacks in Hakkari province, on Turkey’s borders with Iran and Iraq, came after repeated PKK harassment of military outposts in recent days, according to Turkey’s privately owned Dogan news agency.

“Around Daglica in Hakkari, very serious harassment fire took place,” Prime Minister Ahmet Davutoglu said Tuesday in Ankara. “It is impossible for us to show patience or make concessions against this. Our armed forces took the necessary precautions. The peace talks are not an alternative to public safety.”

The PKK, which is listed as a terrorist organization by Turkey, the U.S. and the European Union, accused Turkey of breaching the cease-fire with repeated strikes on Monday afternoon, according to a statement published Tuesday on the Kurdish-run Firat news agency.

“With these assaults, the cease-fire has been breached. Our forces did not incur any losses,” the PKK said, adding that Turkey was still flying drones over their camps.

While the military didn’t immediately confirm the operation or provide comment, it said Tuesday on its website that outposts in four provinces have been drawing fire since Saturday. The garrisons “immediately returned fire and silenced the terrorists,” the military said.

Turkish forces and the PKK have sporadically exchanged fire in momentary breaches of a cease-fire that has largely held since March 2013, when jailed PKK leader Abdullah Ocalan called on his militia to halt fighting, in a landmark moment for the peace process. This week’s airstrikes by F-16s mark Ankara’s most decisive operation against the group since then, but it wasn’t immediately clear if it marked a change in official strategy.

Mounting violence between the military and the PKK came just as the government presented its latest proposal to Kurdish lawmakers on Monday, seeking to press ahead with the negotiations to end a three-decade insurgency that has killed 40,000 people.

The bombings follow months of tensions between the military and the PKK, especially as the Kurdish militants increased their activity along Turkey’s porous southern borders to aid their kin in Iraq and Syria.

The strikes also come as Ankara refuses to aid Kurds in their fight against Islamic State in Syria’s Kobani region, straining relations with Kurds in Turkey. Comprising about 18% of the country’s 77 million people, Kurds staged massive protests—including burning schools and attacking businesses and official buildings—across Turkey last week, when more than three dozen people were killed in clashes with the police.

“Peace talks started before Kobani happened and are not tied to any foreign event,” Mr. Davutoglu said earlier Tuesday in the Ankara Parliament. “The peace process will be carried out with determination.”

Obama administration officials, who have been exhorting Turkish officials to get more actively involved in countering Islamic State, avoided expressing any disappointment at Ankara’s decision to strike the Kurdish sites. “It wouldn’t be accurate to loop the two incidents together.…This situation is obviously not without a great deal of complexity,” said State Department spokeswoman Jen Psaki, noting that the Turks had agreed to host a U.S.-run training program for Syrian rebels on its territory.