At least 35 civilians were killed on Saturday as government forces and rebel fighters exchanged fire in Syria's main northern city of Aleppo, a monitoring group said. The Syrian Observatory for Human Rights said the dead included 18 civilians, two of them children, killed in regime air strikes on Al-Maadi and Sheikh al-Lutfi, two rebel-held neighborhoods in east Aleppo. "Seventeen other civilians were killed when rebel groups fired rockets on neighborhoods controlled by the regime, including Suleimaniyah and other areas," the Britain-based group said. Pictures circulating on social media depicted significant damage.

Besides the fire exchange, the also carried out an airstrike as it does frequently on the opposition-held neighborhoods. The air raid struck near a school in an opposition-held neighborhood in the northern city of Aleppo on Sunday, killing at least nine people, including five children, activists said. The Aleppo Media Center and the Britain-based Syrian Observatory for Human Rights said the air raid hit the opposition-held Ansari neighborhood. The bloodshed comes a day after rebel shelling and government airstrikes killed more than 30 people on both sides of the divided city, which is carved into government- and rebel-controlled areas. The Observatory said at least nine people were killed in Sunday's airstrike, and warned that the tally could rise because many of the wounded were in critical condition. The Aleppo Media Center put the death toll at 10 and said dozens of people were wounded.

Also Sunday, the head of the U.N. agency that supports Palestinians visited refugees from the embattled Palestinian camp of Yarmouk in Damascus. The Palestinians fled Yarmouk, where heavy fighting has raged since Islamic State of Iraq and al-Sham (ISIS) militants stormed the district more than a week ago, for a nearby government-controlled area of the Syrian capital. UNRWA chief Pierre Krahenbuhl met with some 120 Palestinians who have found temporary refuge at a school in the Tadamon neighborhood. The Palestinians recalled the humanitarian crisis inside Yarmouk, where residents have already endured a more than two-year government siege, starvation and disease. "The conditions were very difficult," said Rahaf Qadri, who left Yarmouk 10 days ago. "There was no food, and diseases have started to spread." Qadri said her husband is still in the camp, and has joined Palestinian factions trying to protect Yarmouk from the ISIS incursion. Another Yarmouk refugee, 50-year-old Mohammad al-Halabi, deplored the lack of food and electricity in the camp, and said the situation worsened with the attack by ISIS militants. "We saw some people being beheaded and heard gunshots to terrorize people," al-Halabi told The Associated Press. "They warned us that unless we join them, our heads will be cut off. "We refused and later the Palestinian factions came and we left with them," he said.