ISIS slaughters scores in Syrian offensive January 17, 2016 ISIS terrorists advance in Syria. (Raqqa Media Center/AP)(Raqqa Media Center/AP)ISIS slaughters scores in Syrian offensiveAs it continues its westward march, and as the world watches stupefied, ISIS is destroying anything and anyone in its path that does not conform to its twisted worldview. By: AP and World Israel News StaffSyria’s government said Sunday that Islamic State (ISIS) terrorists slaughtered 300 people in an “appalling massacre” committed in the eastern city of Deir el-Zour in daylong attacks that saw ISIS make significant advances in the contested region.The state-run SANA news agency said that most of those killed in Saturday’s attacks were elderly people, women and children, while opposition activists said many of the victims were Syrian soldiers and pro-government militiamen and their families.The killings are some of the worst carried out by ISIS, which controls large parts of Syria and Iraq and has killed thousands of people in both countries.The Britain-based Syrian Observatory for Human Rights (SOHR), which documents all sides of the Syria conflict through activists on the ground, said late Saturday that at least 135 people were killed. It said around 80 of them were soldiers and pro-government militiamen and the rest civilians.It added that many of them were shot dead or beheaded.The Islamic State group controls most of Deir el-Zour province and much of the capital with the same name, while the government controls several districts in the northern part of the city and the adjacent military airport. Most of the casualties took place in the area of Baghaliyeh near the city.Read Israel first attacked radar detection systems to weaken Iran's ability to intercept strikesThe Lebanon-based Hezboolah-linked Al-Mayadeen TV, which is close to the Syrian government, also reported a massacre and said ISIS killed dozens of people, including women and children, and threw their bodies in the Euphrates River. It said the group took more than 400 civilians hostage.The reports could not be independently confirmed.The ISIS-affiliated Aamaq news agency had reported a large-scale multi-pronged attack on Deir el-Zour that began with a suicide bombing. On Sunday, it reported that the group expanded its control of areas west and northwest of Deir el-Zour, adding that around 110 Syrian government forces were killed and at least five others captured.It said the group seized control of Baghaliyeh and surrounding areas during the fighting.Since declaring the establishment of its Muslim “caliphate” in June 2014, ISIS has executed more than 3,500 people in Syria, including nearly 2,000 civilians.These numbers do not include ISIS’ atrocities in Iraq, which is also partially under its control. Also, they do not include the 800 lives ISIS has taken in terror attacks around the globe.More than 250,000 people have been killed and more than four million have fled the country since the Syrian civil war erupted in 2011. Deir el-ZourISISIslamic StateIslamic terrorSOHRSyriaSyrian Civil War