A bomb blast hit a bus convoy waiting to cross into government-held Aleppo in Syria on Saturday, killing hundreds of people evacuated from two Shi'ite villages the day before in a deal between warring sides.
The bomber targeted buses full of evacuees from government-held towns as they waited in a rebel-held area on the outskirts of Aleppo. He drove his explosives up to their vehicles in a van meant to carry aid supplies.
The Syrian Civil Defence in Aleppo province, also known as the White Helmets, said their volunteers pulled at least 100 bodies from the site of the explosion. White Helmets member Ibrahim Alhaj said the dead included many children and women
The blast hit buses in the Rashidin area on Aleppo's outskirts. The vehicles had been waiting since Friday to cross from rebel-held territory into the government-controlled city itself. Ambulances later took the wounded to hospital in Aleppo.
The convoy was carrying residents and pro-government fighters from the Shi'ite villages of al-Foua and Kefraya, which are besieged by rebels in nearby Idlib province, an insurgent stronghold.
They had left under a deal where, in exchange, hundreds of Sunni insurgents and their families were granted safe passage from Madaya, a government-besieged town near Damascus.
The "Four Towns" deal brokered by Iran and Qatar was meant to relieve suffering in besieged towns - Foah and Kefraya in the north-west which are under government control, and rebel-held Madaya and Zabadani, near Damascus.
More than 300,000 people have lost their lives and millions of people have been displaced since a peaceful uprising against President Bashar al-Assad six years ago turned into a full-scale civil war.
More than 80 people were killed in a suspected chemical attack on the rebel-held town of Khan Sheikhoun, in the north-west, on 4 April, prompting the US to bomb a government air base with missiles.
Russia and Iran also have military forces deployed in the country, backing President Assad.