South Korea's military Wednesday staged a live-fire artillery exercise on an island hit by a deadly North Korean bombardment last November, officials said.
The exercise on Yeonpyeong island near the tense Yellow Sea border began at 9.30 am (0030 GMT) and was scheduled to last about one hour, a defence ministry spokesman said.
Tensions along the disputed border have been acute since the shelling last November 23 killed two marines and two civilians and damaged dozens of homes. It was the first attack on a civilian area in the South since the 1950-53 war.
Pyongyang said it was responding to a South Korean artillery drill which dropped shells earlier that day into waters claimed by the North.
Wednesday's drill was the first since a live-fire exercise on Yeonpyeong last December 20. That passed off without incident despite the North's threats to hit back.
A similar live-fire drill was being carried out Wednesday on Baengnyeong island, the closest one to the North's coastline.
The exercises involve K-9 self-propelled howitzers, Vulcan cannons and 81mm mortars, according to the Marine Corps which garrisons the frontline islands whose defences have been strengthened since last November.
Guns were being aimed southwards, away from the North.
