Ankara: Turkish warplanes struck against Kurdish militant camps in northern Iraq on Monday after 37 people were killed in an Ankara car bombing that security officials said involved a female fighter of the Kurdistan Workers Party (PKK).
Sunday's attack, tearing through a crowded transport hub a few hundred metres (yards) from the Justice and Interior Ministries, was the second such strike at the administrative heart of the Turkish capital in under a month.
Security officials told Reuters a female member of the outlawed PKK, which has fought a three-decade insurgency for Kurdish autonomy in Turkey's southeast, was one of two suspected perpetrators.
A police source said her severed hand had been found 300 metres from the blast site. Evidence had been obtained that suggested she was born in 1992, was from the eastern city of Kars near the Armenian border, and had joined the militant group in 2013, they said.
Meanwhle state-run Anadolu Agency reported that police had detained four people in southeast turkey on Monday in connection with the vehicle used in Sunday's car bomb attack in the capital Ankara which killed 37 people.
It cited security sources as saying the four were detained in the city of Sanliurfa, situated north of the Syrian border, after they established that the vehicle was bought from a car showroom there. The four suspects were to be taken to Ankara, it added.
Violence has spiralled in Turkey's predominantly Kurdish southeast since a 2-1/2 year ceasefire with the PKK collapsed in July. The militants have so far largely focused their strikes on security forces in southeastern towns, many of which have been under curfew. But attacks in Ankara and in Istanbul over the last year, and the activity of IS as well as Kurdish fighters, have raised concerns among NATO allies who see Turkey's stability as vital to containing violence in neighbouring Syria and Iraq.
President Tayyip Erdogan is also eager to dispel any notion he is struggling to maintain security.
"With the power of our state and wisdom of our people, we will dig up the roots of this terror network which targets our unity and peace," Foreign Minister Mevlut Cavusoglu said on Twitter.
The Turkish military said 11 warplanes carried out air strikes on 18 targets in northern Iraq early on Monday, including ammunition depots and shelters.
The PKK has its bases in the mountains of northern Iraq, controlling operations across the frontier in Turkey. A round-the-clock curfew was declared in three southeastern towns in order to conduct operations against Kurdish militants, local officials said. Many locals fled the towns in anticipation of the operations.
Victims of Sunday's attack included the father of Umut Bulut, a footballer who plays for Turkey and Galatasaray, the Istanbul club said on its website.
"It is clear that Turkey's political risk profile is rising gradually and the country is not yet safe for long-term investors," Atilla Yesilada of Istanbul-based consultancy Global Source Partners said in a note to clients. The German foreign ministry issued a travel warning for Turkey of potential terrorist attacks. In its armed campaign, the PKK has historically struck directly at the security forces and says it does not target civilians. A direct claim of responsibility for Sunday's bombing would indicate a major tactical shift. The Kurdistan Freedom Hawks (TAK) claimed responsibility for the February bombing. TAK says it has split from the PKK, although experts who study Kurdish militants say the two are affiliated.