Afrin District
Following YPG successes in 2015, including the capture of Tell Abyad, Turkey began targeting YPG forces in northern Syria. On 16 February 2016, Turkish forces began shelling Kurdish forces in the Afrin District after the SDF took initiative from an SAA offensive and captured rebel-held areas of the Azaz District, including Tell Rifaat and Menagh Airbase. Turkey vowed not to allow the SDF to capture the key border town of Azaz. As a result, 25 Kurdish militants were killed and 197 injured from Turkish artillery fire. In early 2016, following the capture of Tishrin Dam, the Syrian Democratic Forces (SDF) were allowed to cross the Euphrates River, a proclaimed 'red line' by Turkey. Turkish forces bombed the Kurdish YPG headquarters in Tell Abyad, destroying three armoured vehicles and injuring two Kurdish fighters. The following day, 21 January 2016, Turkish troops crossed the border into Syria and entered the ISIL-controlled Syrian border town of Jarabulus which the YPG had been planning on capturing as part of an offensive to unite their areas of control into one continuous banner of territory. Kurdish-led forces in northern Syria said Turkish airstrikes hit their bases in Amarneh village near Jarablus on 27 August 2016, after Turkish artillery shelled the positions the day before. The Syrian Observatory reported on 27 August 2016, about exchange of gunfire between YPG and the Turkish forces in the countryside north of Hasakah. It is unclear if Turkish forces were on Syrian territory or had fired across the border.