N Korea conducts 'underwater nuclear weapons system' test - state media (BBC)

North Korea has carried out a test of its underwater drone allegedly carrying a nuclear weapon this week, in response to the US, South Korea and Japan drills.

South Korea says these claims are ‘provocation’ and that the North’s defense science level is not developed enough to pose a significant risk threat.

North Korea has reportedly had a history of repeated unsupported claims on their military power; designating the South as their ‘principal enemy’ and that war could ‘break out any time’.