South Korean military sharpens reflexes on divided peninsula

YEONCHEON, South Korea (Reuters) - As North Korea prepares a third nuclear test, South Korean soldiers on the world's most heavily armed border now have orders to shoot back immediately if they come under attack, a move that risks escalating any small-scale conflict.

Stung by criticism three years ago of the time it took South Korean artillery to respond to a burst of shelling from the North, Seoul's Defence Ministry has relaxed rules that required officials at its command centre to sanction a response.