North Korea made a false claim about the April 23 launch of its submarine-launched ballistic missile (SLBM), multiple government sources in Seoul were quoted by Yonhap as saying on Sunday

They added that the missile is presumed to have exploded in the air.

The 30 km is far below SLBMs' minimum range of 300 kilometers, the source added.

North Korea's media claimed on April 24 that it successfully launched an SLBM the previous day in the presence of leader Kim Jong-un that can greatly advance the fighting capability of its navy. 

It quoted Kim as saying that with the SLBM launch, the North now possesses a powerful nuclear weapons arsenal and a credible delivery system. 

Source ; MENA