sentences:  After 7 February, the clashes also included Jund al-Aqsa as a third belligerent, which had re-branded itself as "Liwa al-Aqsa" and was attacking the other combatants.The battles were fought in the Idlib Governorate and the western countryside of the Aleppo Governorate.The Khan Shaykhun chemical attack took place on 4 April 2017, on the town of Khan Shaykhun, then under the control of Hayat Tahrir al-Sham (HTS).