Seoul, May 26 (IANS): North Korea is building artillery positions in an uninhabited island just above the inter-Korean maritime border, South Korean military said on Tuesday.

Defence Ministry spokesman Kim Min-seok said that North Korean military is constructing facilities in the island of Gal, some 4.5 km north of the South Korea's border island of Yeonpyeong, Xinhua news agency reported.

Given the Gal island's geopolitical position and the close distance from the Yeonpyeong island, North Korea's facilities would pose a serious threat to the South Korean military's operation near the Northern Limit Line (NLL), Kim said.

The NLL, which was drawn by the US-led forces after the 1950- 53 Korean War ended in a ceasefire, has served as a de-facto maritime border between the two Koreas, which the North Korea claimed must be redrawn farther south.

The South Korean military authorities said that North Korea has already completed the construction of five bunker-shaped positions for 122-mm multiple rocket launchers.

The 122-mm multiple rocket launchers were mobilised when Pyongyang carried out an artillery strike against the Yeonpyeong island in November 2010 and killed two South Korean civilians and two marines.