During the Battle of Mosul (2016–2017), numerous reports of human rights abuses surfaced against the various parties involved in the conflict. Up to 1.5 million civilians lived in the city, sparking concerns among various organizations of a large humanitarian crisis. Lise Grande, the United Nations' humanitarian coordinator in Iraq, stated, "In a worst-case scenario, we're literally looking at the single largest humanitarian operation in the world in 2016." Save the Children warned that massive civilian bloodshed was likely, unless safe routes were authorized to let civilians flee. The U.S. government has accused ISIL of using civilians as human shields. Human rights abuses ISIL abuses, abductions and atrocities Fears that civilians could be used as human shields by ISIL were realized as it was confirmed the group had been abducting civilians from villages for this purpose, which received widespread condemnation from human rights groups and the United Nations Security Council. ISIL has reportedly threatened to execute civilians trying to flee. Snipers, landmines, toxic weapons and trenches were preventing people from attempting to escape. Iraqi officials, via radio broadcasts and leaflets dropped over the city, warned civilians to stay in their homes. Leaflets advised residents of various precautions to take including instructions to tape over their windows to protect from flying glass and to disconnect gas pipes. Shortly after the battle began, news surfaced of ISIL kidnapping and executing civilians in Mosul. Pentagon spokesman Capt. Jeff Davis stated that ISIL was using civilians as human shields and holding people against their will in the city. The International Business Times reported that ISIL has forced boys from Mosul as young as 12 to fight for them, and that ISIL had trained the children to "behead prisoners and make suicide bombs". An Iraqi intelligence source stated on 21 October that ISIL executed 284 men and boys abducted from Mosul for the purpose of using them as human shields. The civilians were shot and put in a mass grave. A United Nations official said the UN is "gravely worried" about the fate of 200 families from Somalia and 350 families from Najafia who were abducted Monday by ISIL, who could be used as human shields. UN sources stated that four people died from inhaling toxic fumes after ISIL set fire to the Al-Mishraq Chemical Factory on 23 October. On 26 October, CNN reported that ISIL has been carrying out "retribution killings" of civilians as revenge