Syria conflict: IS assault halts Deir al-Zour aid drops
The World Food Programme has suspended air drops of aid to the eastern Syrian city of Deir al-Zour, which is besieged by so-called Islamic State (IS).
A spokeswoman said heavy fighting between Syrian government forces and IS militants around the landing zone meant it was "simply too dangerous".
Some 110,000 people are trapped in a government-held enclave in the city.
IS was reported to have cut off the enclave from a nearby military base after launching an offensive on Sunday.
Almost 120 people are reported to have been killed in the fighting.
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The WFP has carried out 177 air drops over government-held Deir al-Zour since last April, dispatching a total of 3,300 tonnes of food and other aid supplies.
The cargo is usually dropped into a zone on the outskirts of the city and is picked up by WFP's partner on the ground, the Syrian Arab Red Crescent (SARC).
The last air drop was on Sunday, after which the operation was temporarily suspended "for security operational reasons", spokeswoman Bettina Luescher told reporters in Geneva.
"There is heavy fighting ongoing in and around the landing zone," she explained. "It is simply too dangerous to do this now."
The IS assault, which included waves of suicide bombers, is the most violent in the area in more than a year, according to the Syrian Observatory for Human Rights.
The UK-based monitoring group said on Tuesday that the fighting had left at least 116 people dead, including 21 civilians and 37 members of government forces.
The official Sana news agency said tens of militants had been killed by army units on Monday, but did not report any fatalities among government forces.
The Syrian Observatory said the government was flying reinforcements to Deir al-Zour's military base and had called on locals to take up arms.
Syrian and Russian warplanes were also carrying out air strikes on IS positions.
IS militants advanced into Deir al-Zour in 2015 and imposed a siege last year, seeking to oust government forces form the airbase and neighbouring districts along the River Euphrates.
Last month, the jihadists regained control of the ancient city of Palmyra, about 185km (115 miles) south-west of Deir al-Zour, despite heavy Russian air strikes backing up government troops.