North Korea fired more than 200 artillery rounds into the sea on Friday near a tense maritime border with South Korea, a military official said, while residents of two South Korean islands were ordered to seek shelter due to an unspecified "situation."
North Korea said its drills were a natural response to large-scale military actions by the South Korean military "gangster" and had no impact on the safety of South Korean islands, official news agency KCNA said.
The defense ministry would not confirm if the order was prompted by the North's artillery firing or South Korean drills in response.
However, a text message sent to residents and confirmed by an island official cited "naval fire" to be conducted by South Korean troops from 3 p.m.(0600 GMT) Friday.
An official on Yeonpyeong island, which sits just south of the disputed Northern Limit Line (NLL) sea border, said the evacuation was ordered for residents to move into shelters on the island at the request of the South Korean military.
The firing by North Korea caused no civilian or military damage in the South, South Korea's military said in a news briefing.
"This is an act of provocation that escalates tension and threatens peace on the Korean peninsula," a spokesman for the South Korean Joint Chiefs of Staff said.
The North Korean artillery shells all landed on the northern side of a disputed maritime border, the spokesman, Lee Sung-joon, said, adding the South Korean military has been monitoring the North's moves along its shores with the cooperation of the U.S. military.
He warned the South will take "corresponding measures" in response to the North's actions.
Disputed Waters
South Korea's military told the village there was firing at sea by the South Korean military after "a situation" near the border, the official said. But it was not clear whether it was a drill or had some other cause.
Yeonpyeong is home to just over 2,000 residents and troops stationed there, about 120 km (75 miles) west of Seoul and accessed by ferries taking more than 2-and-a-half hours.
The waters near the disputed NLL have been the site of several deadly clashes between the North and South Korea including skirmishes involving warships and the sinking of a South Korean navy corvette early in 2010 by what is believed to be a North Korean torpedo.
In November 2010, North Korean artillery fired scores of rounds at Yeonpyeong island, killing four people, including two civilians, in one of the heaviest attacks on its neighbor since the Korean War ended in 1953.
North Korea said at the time it was provoked into the attack by South Korean live-fire drills that dropped shells into its territorial waters.
Drawn up at the end of the 1950-53 Korean War as an unofficial border, Pyongyang did not dispute the NLL until in the 1970s, when it began violating the line and arguing for a border further to the south.
Residents of Baengnyeong island which lies far to the west of Yeonpyeong and also near the sea border, were also told to seek shelter, a village official there said. Its population is about 4,900.
North Korea has increasingly warned in recent days that the situation on the Korean peninsula is spiraling towards war because of dangerous moves by the US and South Korean militaries.
Both Koreas have vowed crushing military responses if attacked.
In November, the North declared an agreement signed by the two Korea's leaders in 2018 aimed at de-escalating tension and prevent accidental outbreak of war was no longer valid, after the South said it would resume drills near the border.
The two sides had agreed to cease military drills near the border including the sea borders off the west and east coasts.
South Korea conducts "corresponding" drills in response
South Korea's military conducted "corresponding" live firing drills on Friday in response to North Korea's firing of artillery rounds into the sea near a disputed maritime border, the South's defence ministry said.