SYRIA began three days’ national mourning today as the scale of a terrorist attack on an army graduation ceremony became clear.

Thursday’s drone attack on the Homs Military Academy killed 89 people, including 31 women and five children, and wounded 277, the Health Ministry confirmed. More deaths are anticipated as some of the wounded are in critical condition.

Hundreds of people, many of them dressed in black and weeping, gathered outside the Abdul-Qader Shaqfa Military Hospital where the bodies of 30 victims in coffins draped with Syrian flags were put in ambulances to be taken to their home towns for burial.

Defence Minister General Ali Abbas said to families of victims outside the hospital: “We will go after them and those who support them. We will avenge the blood of martyrs and clean Syria’s soil of terrorists and criminals.”

No group has claimed responsibility for the blast. Though the Syrian government has regained control over most of the country following years of civil war, it remains in a simmering conflict with jihadist groups running a Turkey-backed regime in the north-west, while parts of the north-east are under control of Kurdish groups themselves periodically bombed by Turkey but allied to US forces which remain in the country. Syria has also proved incapable of preventing periodic Israeli air raids on its territory.

Homs is around 60 miles south of jihadist-controlled territory and Syrian officials will fear the rebel administration in Idlib may have gained access to longer-range weaponry. 

Exchanges of fire between Syrian and rebel positions intensified today. The jihadist-aligned White Helmets group said at least four people were killed by Syrian military bombardments overnight, while the Britain-based Syrian Observatory for Human Rights said Russian jets had launched bombing raids over the town of Jisr al-Shughour and nearby villages controlled by the Turkistan Islamic Party, a Uighur extremist organisation. 

Russia maintains a major military base in Syria and, with Iran, is the government’s main ally. Thousands of Uighur separatists travelled to Syria from China to take part in the civil war there, viewing it as part of a wider international struggle to establish an Islamist caliphate.