Assad regime warplanes carried out several air strikes and low-level clashes persisted in some areas on Sunday, but a Turkish- and Russian-backed ceasefire largely held in other areas on its third day, a monitoring group and opposition fighters said. Jets bombed the villages of Kafr Kar, Mintar and around the town of Banan in the southern Aleppo countryside, the British-based Syrian Observatory for Human Rights said. It said Assad regime forces also advanced overnight against opposition fighters in the Eastern Ghouta area near Damascus, seizing 10 farms. But opposition groups did not follow through on threats made on Saturday to abandon the truce altogether, raising hopes for an end to almost six years of fighting. A military news outlet run by Lebanese group Hezbollah, an ally of the Assad regime, said the regime had destroyed an armored vehicle belonging to the former Nusra Front in southern Aleppo province. Mohammed Rasheed, a spokesman for the Jaish al-Nasr group operating mostly in the western province of Hama, said the area was mostly calm. There were low-level clashes in Wadi Barada near Damascus but regime forces and their allies had stopped carrying out air strikes and shelling, he said. The Hezbollah-run news outlet said during the night that regime forces were fighting against the former Nusra Front in that area and had killed several militants. The opposition fighters warned on Saturday they would abandon the truce if Assad regime’s truce violations persisted, giving an 8 p.m. (1800 GMT) deadline for attacks in Wadi Barada to stop. The shelling and air raids ceased by that time, rebels said.

The Turkey and Russia-brokered cease-fire agreement came into effect in Syria at midnight on Dec. 29, and the implementation of the truce has increased hopes that the Astana meeting might pave the way for a peace settlement to end years of civil war. Syrian opposition also welcomed the cease-fire.

The cease-fire does not cover groups designated by the U.N. Security Council as terrorist organizations, such as Daesh and the Nusra Front.