An unknown explosive device has detonated in a bus in Volgograd, 1,000km to the south-east of Moscow, killing at least five people and injuring 20. A terrorist attack is now viewed as the cause of the blast. A terrorist act has been confirmed by the National Anti-terrorist Committee. “Today at 2:05pm Moscow time [10:05 GMT] in Volgograd inside a bus, as a result of an unknown explosive device going...