At least 16 civilians were killed Sunday when Syrian troops loyal to President Bashar al-Assad shelled a town in the centre of the country, an opposition group said. The deaths included three children in the town of Souran in the province of Hama, the London-based Syrian Observatory for Human Rights said. Government troops stormed the town and fired randomly on people. Elsewhere, an explosion occurred near a convoy carrying the chief of the United Nations observer mission, Major General Robert Mood, in Douma near the Syrian capital Damascus, the Dubai-based broadcaster Arabiya reported.