Syrian forces have reached troops besieged for years in the eastern city of Deir al-Zor, one of ISIL’s last major strongholds. State media reports the Army and its allies pushed their way swiftly through to a government-held enclave where thousands of civilians and Syrian forces had been held captive since 2014.

The group still retains a grasp on half of the city and much of Deir al-Zor province. But the military has hailed the breakthrough part of “a strategic transformation in the war against terrorism.”

Military General Command spokesman, Ali Mihoub, said it confirms the capabilities of the Syrian Arab Army and its allies, and their determination in dealing a complete blow to terrorism in Syria and plans to divide Syria.”

A Russian frigate involved in the offensive fired Kalibr cruise missiles from the Mediterranean, destroying key positions, its defence ministry said. Moscow claims it was targeting ISIL fighters from Russia and the former Soviet Union.