Thirteen Turkish soldiers were killed Sunday by Turkish Workers Party (PKK) fighters in Sirnak province in the country's south-east, Turkish media reports said according to DPA. The soldiers had been involved in operations against the outlawed PKK, who have been the object of a government-backed major offensive over the past several weeks. A security agreement was recently reached by Baghdad and Ankara, under which Baghdad pledged to cooperate with Ankara in efforts to crack down on Kurdish rebels based in northern Iraq. The agreement, reached without the consent of the government of the autonomous region of Kurdistan, does not allow Turkey to launch military operations against Kurdish rebels across the border.