In Syria, Government forces are closing in on the eastern city of Deir al-Zour, which has been besieged by so-called Islamic State for almost three years. State Television said a rapid advance through the desert had brought troops to within three kilometers of the government-held enclave in the city's west. <br/><br/>An estimated 93,000 civilians are living in the government enclave in Deir al-Zour. The Syrian troops are also reported to have reached the edge of the government-held Brigade 137 military base, close to Deir al-Zour. <br/><br/>Meanwhile, two Russian soldiers were killed in an IS mortar attack in Deir al-Zour province. Russian Defence Ministry said the convoy was transporting Russian ceasefire monitoring military staff when it came under mortar attack.<br/><br/>IS controls half of Deir al-Zour and much of its surrounding province. It is the jihadist group's last major stronghold in Syria, with the de facto capital of Raqqa under siege by a US-backed alliance of Syrian Kurdish and Arab fighters.