Beirut — A Syrian regime airstrike hit a school in the main northern city of Aleppo on Sunday killing five children and four other civilians, a monitoring group said. “Military aircraft struck a school in east Aleppo city and killed five children, three female teachers and one man,” said Rami Abdel Rahman, head of the Syrian Observatory for Human Rights. He said a number of people were seriously wounded and the death toll was likely to rise. Another child was killed in an airstrike on a rebel-held neighborhood of east Aleppo, the Britain-based Observatory reported. The strikes come after a day after government forces and rebel fighters exchanged fire in the northern city, leaving at least 35 civilians dead. Many schools in Aleppo city have been forced to close, while others hold classes in basements. Meanwhile, the head of the UN agency responsible for Palestinian refugees called from Damascus on Sunday for safe passage for people wishing to leave the Yarmouk camp on the city fringes that Daesh (the so-called IS) is trying to take over. UNRWA Commissioner General Pierre Krahenbuhl and another senior UN official are in the Syrian capital to find ways to ease the plight of some 18,000 people estimated to be trapped in Yarmouk, which has been under government siege since 2013. A Syrian military source said the army was giving a chance for solutions aimed at resolving the situation in Yarmouk, which UN Secretary General Ban Ki-moon has said is "beginning to resemble a death camp". Ban said last Thursday that residents of Yarmouk were being "held hostage" by the Daesh militants and other extremists. He also said they "face a double-edged sword — armed elements inside the camp, and government forces outside". — Agencies