North Korea ‘tests nuclear-capable drone that can trigger radioactive tsunamis’

A purported underwater blast of a test warhead loaded to an unmanned underwater nuclear attack craft during an exercise around Hongwon Bay in waters off North Korea’s eastern coast (Korean Central News Agency/Korea News Service/AP)

North Korea claims to have tested a nuclear-capable underwater drone that can generate a gigantic “radioactive tsunami” and destroy naval strike groups and ports.

Analysts are sceptical the device presents a major new threat but the test underlines the North’s commitment to raising nuclear threats.