(Reuters) – A group monitoring the Syrian war said at least nine people including five children were killed in a Syrian army air strike that hit a school in a rebel-held area of the country’s second city Aleppo on Sunday, though the army denied the report. A Syrian army source told Reuters the army had stepped up attacks on rebels since the insurgents bombarded a government-held residential area in the northwestern city on Saturday. But he said the military had not targeted civilians.