Mount Sinjar. Also, five days later, Kurdish Peshmerga ground troops, with the help of Iraqi Special Forces and the US air campaign, overran ISIL militants and reclaimed the Mosul Dam. On 31 August, the United States, France, United Kingdom and Australia began humanitarian aid drops of food, water and medical supplies to help prevent a potential massacre against the Shia Turkmen minority in Amirli. The US also carried out air strikes on ISIL positions around and near Amirli. Iraqi officials stated that they had reached Amirli and broken the siege and that the military was fighting to clear the areas around the town. This is known to be the first major turning point against ISIL in Iraq. In September, the United States sent an additional 250 troops to protect American personnel, while the first engagement of the British military against ISIL targets took place when a British Panavia Tornado jet dropped a Paveway IV bomb on "a heavy weapon position" operated by ISIL in northwest Iraq at the end of the month. In addition, Australia offered 200 special forces to the Kurds and 600 Australian troops landed in the UAE. The following month, Australia authorized its special forces troops to go to Iraq as part of the anti-ISIL coalition that day, as well as authorizing airstrikes. In mid-October ISIL forces captured the city of Hīt after the 300-strong Iraqi Army garrison abandoned and set fire to its local base and supplies. As a result, an estimated 180,000 civilians (including refugees of the previous Anbar offensive) attempted to flee the area. Later that month, Operation Ashura was launched by Iraqi forces and Iranian-backed Shia militias, scoring a major victory and retaking the strategic town of Jurf al-Sakhar near Baghdad, and securing the way for millions of Shia pilgrims who were going to Karbala and Najaf On the Day of Ashura. Kurdish forces, meanwhile, recaptured Zummar. On 21 October, ISIL seized terrain north of the Sinjar Mountains, thus cutting the area's escape route to Kurdish areas. The Yazidi militias then withdrew from there into the mountains, where the number of Yazidi civilian refugees was estimated at 2,000–7,000. The mountains had once again been partially surrounded by ISIL. In mid-November, Iraqi forces retook control of most of the strategic city Baiji from the Islamic State and broke the siege of the nearby oil refinery. However, by the following month, ISIL recaptured Baiji and