Turkey struck a senior Kurdistan Workers Party official at a refugee camp in northern Iraq, state-owned Anadolu news agency said on Friday, in the second such attack in less than a week.
It said Hasan Adir was "neutralised" in an operation by Turkey's intelligence agency near Makhmour refugee camp, which is located 180 km (100 miles) inside Iraq and has been a shelter for thousands of Turkish Kurds since the 1990s.
The strike came five days after President Tayyip Erdogan said a Turkish air strike had hit another PKK official at Makhmour, which he described as "an incubator for terrorism".
Turkey says the PKK, designated a terrorist organisation by the United States and European Union, has used bases in northern Iraq as safe havens during its decades-long insurgency in southeast Turkey.
Turkey has stepped up operations against the PKK inside Iraq, establishing military bases and deploying armed drones against the fighters in their mountain strongholds.
U.S. ambassador to the United Nations Linda Thomas-Greenfield, who visited Ankara a week ago, said she had told Turkish officials during her talks that any attack targeting civilians at Makhmour would violate international law.
A senior Turkish security source said last week's air strike did not take place in a civilian area, and warned that attacks on PKK targets would continue.
The camp was established in the 1990s when thousands of Kurds from Turkey crossed the border in a movement Ankara says was deliberately provoked by the PKK.
(Reporting by Ezgi Erkoyun; Writing by Dominic Evans; Editing by Jonathan Spicer)
