In response to rapid territorial gains made by the so-called Islamic State during the first half of 2014, and its universally condemned executions, reported human rights abuses and the fear of further spillovers of the Syrian Civil War, many states began to intervene against it in both the Syrian Civil War and the War in Iraq. Later, there were also minor interventions by some states against IS-affiliated groups in Nigeria and Libya. In mid-June 2014, Iran, according to American and British information, started flying drones over Iraq, and, according to Reuters, Iranian soldiers were in Iraq fighting IS. Simultaneously, the United States ordered a small number of troops to Iraq and started flying crewed aircraft over Iraq. In July 2014, according to the International Institute for Strategic Studies, Iran sent Sukhoi Su-25 aircraft to Iraq, and Hezbollah purportedly sent trainers and advisers to Iraq in order to help Shia militias to monitor ISIL's movements. In August 2014, the US and Iran separately began a campaign of airstrikes on ISIL targets in Iraq. Since then, fourteen countries in a US-led coalition have also executed airstrikes on ISIL in Iraq and in Syria. In September 2015, Russian forces, with the permission of the Syrian government, began thousands of bombing raids against ISIL, al-Nusra Front, and the Free Syrian Army (FSA). In the months following the beginning of both air campaigns, ISIL began to lose ground in both Iraq and Syria. Civilian deaths from airstrikes began to mount in 2015 and 2016. In mid-2016, the US and Russia planned to begin coordinating their airstrikes; however, this coordination did not materialize. As of December 2017, ISIL was estimated to control no territory in Iraq, and 5% of Syrian territory, after prolonged actions. On 9 December 2017, Iraq declared victory in the fight against ISIL and stated that the War in Iraq was over. On 23 March 2019, ISIL was defeated territorially in Syria after losing the Battle of Baghuz Fawqani, after which the group was forced into an insurgency. ISIL's leader, Abu Bakr al-Baghdadi, died during a US special operations raid in northern Syria in October 2019 and was succeeded by Abu Ibrahim al-Hashimi al-Qurashi. The United Nations estimated in August 2020 that over 10,000 ISIL fighters remained in Syria and Iraq, mainly as sleeper cells. International coalitions against the Islamic State US-led coalitions On the margins of the 4/5 September 2014 NATO summit