SEOUL, Oct. 12 (Yonhap) -- South Korea's military has stepped up its combat readiness after detecting unusual military movement by North Korea's armed forces along the tense western sea border, Seoul officials said Wednesday.

Seoul recently discovered that the North's military had relocated a ground-to-air missile to north of the South's northernmost island of Baengnyeong. In addition, Pyongyang has moved the missile's movable launching pad to a missile base near the western sea border, a senior government official said, requesting anonymity.