Syrias Kurds on Wednesday said they had captured eight alleged foreign militants including an American teenager in fighting against the ISIS terrorist group. The eight, detained on Sunday and Monday, include a 16-year-old American, as well as a German and a Russian, the Kurdish Peoples Protection Units (YPG), said in a statement. Two are from Uzbekistan. The others are from Tajikistan, Ukraine and Kazakhstan. The YPG has spearheaded the battle against ISIS in eastern Syria, where they are close to flushing out the extremists from their last pocket near the Iraqi border. They are the largest component in the Syrian Democratic Forces (SDF), who are backed by the US-led coalition against ISIS. The YPG published mugshots of the eight alleged foreign jihadist fighters, and gave their names. The announcement comes after the SDF on Monday said they had captured two Americans among five alleged foreign militants on December 30. The Kurds in northeastern Syria say they hold around 1,000 foreign radical fighters, as well as 550 foreign women and 1,200 children who lived with them. They are from dozens of different nationalities and include a significant contingent from France, the main US partner in the coalition assisting Kurdish forces. The numbers of US militants held by the Kurds are believed to be small. The SDF, backed by coalition air strikes, in September launched an offensive to oust ISIS from the last rump of the once-sprawling "caliphate" it proclaimed in 2014. The Kurdish-led forces have since advanced slowly, but ISIS extremists are still holding on to a handful of villages on the eastern banks of the Euphrates River.