North Korean troops performed artillery drills near the disputed sea boundary with South Korea at the order of leader Kim Jong Un.
The North's Korean Central News Agency (KCNA) said that the firing happened when Kim inspected a military unit off the west coast. It was Kim's first known trip to a front-line military unit since he entered nuclear talks with the United States last year.
The
nuclear negotiations are largely at standstill now as North Korea steps up pressure on Washington to lift international sanctions and abandon hostile policies on the North.
South Korea's Defense Ministry expressed regret over the latest drills, saying they violated last year's inter-Korean deals aimed at lowering military animosities in border areas.