TOPSHOTS Kurdish people observe smoke rising from the Syrian town of Kobane, also known as Ain al-Arab, following an explosion as seen from the southeastern Turkish village of Mursitpinar in the Sanliurfa province on October 20, 2014. US President Barack Obama called his Turkish counterpart Recep Tayyip Erdogan and they pledged to step up the fight against the Islamic State group in Syria, the White House said. Kurdish fighters have been under IS assault for more than a month around Kobane, which has become a key prize as it is being fought under the gaze of the world's press massed just over the border in Turkey. AFP PHOTO / BULENT KILIC