MOSCOW (Reuters) - Russia came close to nuclear disaster in late December when a blaze engulfed a nuclear-powered submarine carrying atomic weapons, a leading Russian magazine reported, contradicting official assurances that it was not armed. Russian officials said at the time that all nuclear weapons aboard the Yekaterinburg nuclear submarine had been unloaded well before a fire engulfed the 167-metre (550 feet) vessel and there had been no risk of a radiation leak. But the respected Vlast weekly magazine quoted several sources in the Russian navy as saying that throughout the fire on December 29 the submarine was carrying 16...