BEIRUT - Warplanes mounted a new wave of air strikes on rebel-held areas of Aleppo on Saturday, rebel sources, a rescue worker and a war monitor reported, pressing a major offensive by the Russian-backed Syrian military.Speaking to Reuters from Aleppo, Ammar al Selmo, the head of Civil Defense in the opposition-held east, said: "Unfortunately it continues. There are planes in the sky now."The Britain-based Syrian Observatory for Human Rights Director Rami Abdulrahman told Reuters: "The raids are intense and continuous."Residents of rebel-held eastern Aleppo said it faced the most ferocious bombardment of the war on Friday, after the military declared a new offensive to take back full control of the divided city. Selmo said the death toll was now over 100.The Observatory said its death toll was 47.