Activists say militants have burned at least five buses assigned to evacuate 2,000 wounded and sick people from two villages in northern Syria.

The incident could scupper a wider deal that encompasses the evacuation of thousands of trapped rebel fighters and civilians from the last opposition foothold in east Aleppo.

The opposition's Britain-based Syrian Observatory for Human Rights said Sunday that the al-Qaida affiliated Fatah al-Sham Front burned buses assigned to evacuate people from the rebel-besieged villages of Foua and Kfarya.

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Activists say militants have burned at least five buses assigned to evacuate 2,000 wounded and sick people from two villages in northern Syria

The al-Qaida affiliated Fatah al-Sham Front is thought to have burned buses assigned to evacuate people from the rebel-besieged villages of Foua and Kfarya

Hezbollah, the Lebanese militant group fighting alongside Syria's government, says the buses were burned during fighting between the al-Qaida-affiliated Fatah al-Sham Front and a rebel group that supported the evacuations.

The Observatory says six vehicles were burned while Hezbollah's media outlet put the number at five.

Several thousand civilians evacuated Aleppo on Thursday before the process was halted.

The buses were burned during fighting between the al-Qaida-affiliated Fatah al-Sham Front and a rebel group that supported the evacuations

Several thousand civilians evacuated Aleppo on Thursday, with efforts to get more out of harm's way continuing

The Britain-based Syrian Observatory for Human Rights says six vehicles were burned while Hezbollah's media outlet put the number at five.

Vehicles from the International Red Cross and from the Syrian Red Crescent wait at the government-controlled crossing of Ramoussa

The U.N. Security Council is expected to vote on a resolution demanding immediate access for the United Nations to besieged parts of Aleppo and throughout Syria.

A draft resolution called on Secretary-General Ban Ki-moon to immediately redeploy U.N. staff already on the ground to carry out 'neutral monitoring'.

It stresses that evacuations of civilians 'must be voluntary and to destinations of their choice'.

A member of the pro-government forces monitors the area as buses make their way through Ramoussa

A bus drives through the Syrian government-controlled crossing of Ramoussa, on the southern outskirts of Aleppo