ANKARA, Turkey — Turkish artillery has fired at the Islamic State group across the border in Syria, killing 55 militants and destroying three rocket launchers and three vehicles, the state-run Anadolu Agency reported on Sunday. Meanwhile, Turkish F-16 and F-4 warplanes struck positions of the outlawed Kurdistan Workers Party, or PKK, in northern Iraq, hitting the rebels’ shelters, ammunition depots and weapons emplacements, the agency also reported. The regions targeted included Qandil mountain, where the PKK’s leadership is based. The group has waged a decades-long insurgency against the Turkish state and is designated by Ankara and its allies as a terrorist organization. People hold a national flag with an image of Turkeys founder Kemal Ataturk and a newspaper headline that reads S.O.S. from Kilis: we are dying during a demonstration in Istanbul, Sunday, May 8, 2016. Turkish artillery has fired at the Islamic State group across the border in Syria, [...]