Fighting between ISIS militants and Syrian pro-government forces have intensified in recent days, with reports of ISIS suffering heavy casualties.
The map below accurately displays the situation in Deir-Ezzour, as of the 15th of January. The Syrian Army and allied local militiamen have been besieged by armed militants for several years, with ISIS in the control of most of Deir-Ezzour province.
— Peto Lucem (@PetoLucem) January 15, 2017
Around 4,000 fighters from the elite Republican Guard are defending the city, and the Russian Air Force (RUAF) has played a key role in supplying forces stationed there, as well as providing humanitarian aid to the thousands of trapped civilians.