مقاتلو #الدولة_الإسلامية_في_العراق_والشام المرابطين على جبهة مطار كويرس بريف حلب pic.twitter.com/JTvdublq2O — فطائس حزب اللات (@Syria_homs1) September 7, 2013

Islamic State of Iraq and ash-Sham fighters taking part in siege on Kwiris military airbase in rural Aleppo.

This is the Kwiris Airbase:

The airport, which sets a bit east of Aleppo, is a contested area at the moment. Eastern Aleppo is one of the last remaining areas of northern Syria where the regime still holds control. A large reason for this is the continued control of airbases close to the area that give the regime an edge. If the rebels are able to control the Kwiris airbase, they could gain complete control of Aleppo.