Photo: AFP

Dozens of people have died in an offensive by so-called Islamic State on government-held areas of Deir al-Zour in eastern Syria, local media say, the BBC reports.

The Syrian Observatory for Human Rights said 85 civilians were killed in the attack, as well as 50 Syrian soldiers.

Syria’s state news agency Sana reported that around 300 civilians had died in the Baghaliyeh area of the city.

Meanwhile, the UN warned of “sharply deteriorating conditions” in the besieged areas.

Around 200,000 people were in these areas, the UN Office for the Coordination of Humanitarian Affairs (OCHA) said.