A car bomb has killed three people in southern Russia, according to officials. It is seen as a worrying development six weeks before the country hosts the Winter Olympics.<br /><br />The blast happened at Pyatigorsk in the Russian Caucasus, some 270 kilometres from Sochi where the Games are to take place.<br /><br />The city lies just north of a region which is host to a long-running Islamist insurgency, and where one Chechen warlord urged militants to stop the Olympics.<br /><br />The blast badly damaged a traffic police building. The three victims were reportedly outside; it is not clear whether or not they were police officers.<br /><br />A state of emergency has been declared in the city.
