China warns of war as N.Korea vows 'merciless' response to US

China issued a stern warning Friday that a conflict over North Korea could break out "at any moment", as Pyongyang vowed a "merciless" response to any US military action.Tensions in the region have surged to fresh heights in recent days with speculation mounting that the North is preparing a sixth nuclear test.A US naval strike force has been deployed near the Korean peninsula, and President Donald Trump has issued stark warnings that the threat posed by Pyongyang's nuclear weapons programme "wi