Several buses were set ablaze as they made their way to take civilians out of Shia villages loyal to the Assad regime.
Several buses en route to rescue sick and injured civilians from the northern Syrian villages of Foua and Kefraya were attacked and burned on Sunday, the Syrian Observatory for Human Rights and Syrian regime television said. It is not clear who is responsible for the attack.
Other buses, as well as Red Crescent vehicles, reached the villages in Idlib province, which are besieged by opposition forces. Most of Foua and Kefraya's residents are Shia Muslims. The civil war, now entering its sixth year and having claimed almost half a million lives, has divided the country along bitter sectarian lines, with the majority Sunnis leading the rebellion, and the Shia minority rallying around the Iranian-backed regime, which has the support of Russian air power.
Syrian state media said "armed terrorists," a term it uses for insurgent groups fighting against Assad's rule, attacked five buses and burned and destroyed them. Rebel officials said an angry crowd of people, possibly alongside pro-regime forces, carried out the attack.
A resident in the area told Reuters it was not carried out by the group formerly known as the Nusra Front, which had previously said it had not agreed to the evacuation of the two villages. The evacuation of the villages comes as a part of a deal that will let thousands of residents of eastern Aleppo leave the neighbourhood there and cross into rebel-held Idlib, a target of Russian and regime attacks where the pause in fighting has let civilians resume some semblance of normal life.