The Kurdistan Workers' Party (PKK), a separatist group based in southeast Turkey, has long been considered a terrorist group by both Ankara and Washington. But now, the group is one of the key forces battling the Islamic State (also known as ISIS). Along with the Peshmerga, made of Iraqi Kurds, the PKK has made significant gains against ISIS, including the liberation of the strategic northern Syrian town of Kobani in January. Around 40 percent of PKK fighters are female, some of whom are also in the senior command. In this photo series, women fighters rest and prepare for their next fight at a PKK base on Mount Sinjar in northwest Iraq. In the distance, smoke rises from the front line. Many of the women, who come from all corners of the Kurdish region, have cut links with their families back home.