Dozens of Turkish warplanes struck militant Kurdistan Workers Party (PKK) targets in northern Iraq overnight, killing tens of the group's fighters, a security source told Reuters on Tuesday.
Two government officials said more than 40 jets took part in the strikes, which came after the PKK killed 16 Turkish soldiers in southeast Turkey on Sunday in their deadliest attack since the collapse of a two-year-old ceasefire in July.
The clashes, weeks before polls the ruling AK Party hopes will restore its majority, has left in tatters a peace process which President Tayyip Erdogan launched in 2012 in an attempt to end a three-decade insurgency that has killed more than 40,000.
The security source said F-16 and F-4 jets took part in the air operation which began around 10 p.m. on Monday and continued until 4 a.m., hitting areas around the PKK's bases in Qandil, Basyan Avashin and Zap.
There was no immediate confirmation from the Turkish general staff of the strikes, which the source said hit weapons and food stores as well as gun positions of the PKK.
The PKK, which launched its insurgency in 1984, is designated a terrorist organization by Turkey, the European Union and United States.
(Additional reporting by Orhan Coskun; Writing by Daren Butler; Editing by Nick Tattersall and Alison Williams)