SEOUL - North and South Korea exchanged artillery fire in the Yellow Sea on Thursday, Yonhap News Agency reported, a day after the North threatened to "blow up" South Korean warships in the area in retaliation for an earlier incident.
South Korea's Joint Chiefs of Staff said two North Korean artillery shells fell near a warship patrolling the South Korean side of the de facto maritime border, prompting a South Korean navy corvette to fire five shells into the North Korean side.
The incident reportedly happened around 6 p.m., with the North Korean shells, apparently fired by coastal artillery, falling in waters 14 kilometers south of the South Korean frontline island of Yeonpyeong, Yonhap quoted officials as saying.
Following the incident, the military ordered residents of the island, which in November 2010 was subjected to a North Korean artillery barrage that killed four people, to evacuate to shelters, while fishing boats operating in the area were ordered to return to port.
"The South Korean military is closely watching the North Korean military and preparing against additional provocations," the JCS was quoted as saying, adding that it is looking into the North's motivation for the firing.
North Korea on Wednesday accused South Korea's navy of "firing at random" on its warships the previous day in the Yellow Sea and threatened to target South Korean warships in retaliation.
"From this very moment, all warships of the south Korean puppet navy, big and small, which recklessly maneuver in the sensitive waters of the southwestern front, hot spots, will become without exception targets of the direct sighting firing by all strike means," North Korea's military said in a statement carried by the state-run Korean Central News Agency.
It said those South Korean naval ships are now "targets of physical strikes which should be blown up without fail."
South Korea's JCS said Tuesday that three North Korean military vessels earlier that day briefly crossed the de facto maritime border, prompting the South Korean military to fire warning shots to force their retreat.
North Korea said its ships in that incident were merely checking the illegal fishing operations of Chinese civilian fishing boats in the southwestern waters when they randomly were fired upon.
On April 29, South Korean President Park Geun Hye ordered the military to return fire if shells fired by North Korea amid a drill being held in the Yellow Sea then fell south of the so-called Northern Limit Line, which was drawn by the U.S.-led United Nations Command at the end of the 1950-1953 Korean War.
Pyongyang does not recognize the NLL as legitimate and insists the maritime border be drawn further south.
The area has been the site of several bloody clashes between the two sides.