Turkish warplanes struck against Kurdish militant camps in northern Iraq Monday after 37 people were killed in an Ankara car bombing that security officials alleged involved a female fighter of the Kurdistan Workers Party (PKK).
Sunday's attack, tearing through a crowded transport hub a few hundred meters 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 said a female member of the PKK, which has fought a three-decade insurgency for Kurdish autonomy in Turkey's southeast, was one of two suspected perpetrators.
Violence has spiraled in Turkey's predominantly Kurdish southeast since a cease-fire 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 Islamic State has raised concerns among NATO allies who see Turkey's stability as vital to containing violence in neighboring Syria and Iraq. President Tayyip Erdogan is also eager to dispel any notion he is struggling to maintain security.