A Lebanese TV channel close to the Syrian government is airing footage showing new buses arriving at an evacuation point that was site of a major explosion that killed dozens.
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.
Critics say the string of evacuations, which could see some 30,000 people moved across battle lines over the next 60 days, amounts to forced displacement along political and sectarian lines.
A bomb blast hit a bus convoy waiting to cross into government-held Aleppo in Syria on Saturday, killing and wounding dozens of people evacuated from two Shi'ite villages the day before in a deal between warring sides.The agreement had stalled, leaving thousands of people from both government-besieged and rebel-besieged areas stranded at two transit points on the city's outskirts, before the explosion occurred.Pro-Damascus media outlets said a suicide attacker detonated a vehicle bomb and killed at least 22 people. A war monitor put the death toll at 24 in the area controlled by opposition fighters.
Syrian state TV blamed the rebels for obstructing the deal, causing thousands of evacuees to be stuck in bus depots overnight. Some buses were charred and other gutted from the explosion as belongings hanged out of windows.
The agreement involves Zabadani and Madaya, two government-besieged towns located near the capital Damascus, and Fouaa and Kefraya in northwestern Idlib province, which has been encircled by Syrian rebels since March 2014.More news: Police kill 6 in political violence in India's Kashmir
Ahmed Afandar, a resident evacuated from his home town near Madaya, said dozens of buses carrying women, children and men were not being allowed to proceed toward rebel-held Idlib as planned. A photo carried by al-Ikhbariya state TV showed a number of bodies strewn on the floor with a huge plume of black smoke rising in the background. The deal gave permission for evacuation of more than 2,000 residents, activists and gunmen from areas besieged by government forces.
Around 5,000 people piled onto buses leaving Fuaa and Kafraya while a further 2,200 were evacuated from rebel-held Madaya and Zabadani.
Activists and residents say thousands of Syrians evacuated from their besieged towns have spent the night on buses at an exchange point as a much criticized population transfer deal stalls.
A rebel official said at least 30 of his opposition fighters who were guarding the evacuees were killed in the blast.
"It is a very bad feeling when you see those who besieged you and killed you with hunger and bombardment right in front of you", Maleh said.
Meanwhile, residents and pro-government fighters who had left Fouaa and Kefraya waited in rebel territory on Aleppo's outskirts to cross into the city, the British-based Syrian Observatory for Human Rights (SOHR) said.