North Korea conducts test of underwater nuclear weapons system

The test of the "Haeil-5-23" system, a name North Korea has given to its nuclear-capable underwater attack drones, was carried out by the defence ministry's think tank in the waters off its east coast, the report said, without specifying a date.

The ministry's unnamed spokesman accused the United States, South Korea and Japan of "getting frantic" with military exercises, warning of "catastrophic consequences."

The three countries' navies held their three-day regular drills until Wednesday, alongside the U.S. aircraft carrier Carl Vinson, as part of efforts to improve their responses to Pyongyang's evolving nuclear and missile threats.