North Korea says the artillery attack on South Korea’s Yeonpyeong Island was a self-defense measure.

In a statement by a foreign ministry spokesman, the North said that prior to firing its artillery, the South fired shells toward North Korean waters despite several warnings.

The statement said that South Korea’s claims about the incident imply that it believes all the areas surrounding the island are South Korean territory --- a claim with which the North disagrees.

Regarding international criticism about the North's attack, the North said countries should look into the facts before making any judgments.

The five major Korean islands in the Yellow Sea belong to the South based on the Northern Limit Line maritime border drawn by U.N. forces in 1953. But the North unilaterally set its own maritime military demarcation line in 1999 that extends further south, increasing volatility in the already tense region.