At least 100 people have been killed after explosions struck a convoy of buses carrying Syrian evacuees.
In footage of the immediate aftermath of the blasts seen by IBTimes UK, numerous buses could be seen scorched inside and out with dozens of bodies strewn across the floor.
The current death toll was reported after the Syrian Civil Defence said its volunteers had recovered at least 100 bodies from the scene.
But the initial death toll was reported by the Syrian Observatory for Human Rights and Syrian state TV as 43 people - with both stating the number would be expected to rise sharply throughout the day.
Those aboard were being transported to government-controlled areas of Aleppo after a deal was reached to take civilians out of besieged areas.
It was part of the "Four Towns" deal, brokered by Iran and Qatar, in the hope of ending the plight of civilians living in besieged areas of Syria.
Residents of Al Fu'ah and Kefraya, in militant-controlled Idlib province, were to be transferred to the outskirts of Aleppo, which was recaptured by President Bashar Al-Assad's government last December.
In return, residents of Madaya and Zabadani, living in government-held outskirts of Damascus, were to be transferred to Idlib province.
The blasts hit the buses in the Rashdin area of Aleppo's outskirts and are believed to have been perpetrated by anti-government insurgents. Early reports indicate that the groups were unhappy because certain factions were not included in the deal brokered by Iran and Qatar.
State-controlled news agency SANA reported that 60 buses, carrying an estimated 2,300 people arrived in Idlib province without incident.
The transfers of civilians were temporarily suspended after the attack. The Associated Press reported that they restarted around two hours later.
It is not the first time such convoys have been targeted. When Assad's government recaptured eastern Aleppo in December, buses taking families out of the city were set on fire by militants in order to disrupt the evacuations.