North Korea on Thursday fired two artillery shells near a naval vessel from South Korea on a routine patrol of an area south of the two nations’ disputed maritime boundary in the Yellow Sea, according to reports.
The shells landed in waters some 14 kilometers (9 miles) south of the frontline island of Yeonpyeong, Seoul’s Yonhap news agency reported, quoting South Korea’s Joint Chiefs of Staff.
The North Korean action prompted a South Korean Navy corvette to fire five shells in the vicinity of a North Korean vessel in northern waters.
There were no reports of casualties or damage on the South Korean island from authorities, Yonhap said.
After the incident, fishing boats in the area were ordered to return to nearby ports and residents of Yeonpyeong—where four South Koreans were killed in shelling by the North in November 2010—were evacuated to shelters, the report said.
The agency quoted officials as saying that it was believed the North had fired the shells with coastal artillery, and that the South Korean military was preparing against “additional provocations.”
The exchange of fire, which began around 6:00 p.m. local time, led to a tense standoff between warships from the two sides, but the situation stabilized shortly afterward, Agence France-Presse reported, quoting a South Korean defense ministry spokesman.
Another spokesman told AFP that the ministry had sent a message of protest to North Korea through a military hotline.
The latest incident took place after three North Korean military vessels briefly crossed the disputed maritime border on Tuesday, prompting the South Korean military to fire warning shots, forcing them to retreat.
A day later, Pyongyang threatened to "blow up" any South Korean warships and accused the South of "a grave provocation," saying its vessels had been trying to contain Chinese fishing boats illegally operating in the area.
Young Hyun Kim, a professor of North Korean studies at Dong Kook University in Seoul, told RFA’s Korean Service that Pyongyang was increasingly responding to a tough stance from South Korean government officials towards cross-border affairs through the use of its military.
“This can be seen as a low-intensity armed protest by Pyongyang to test the strength of Seoul’s will to improve inter-Korean relations,” he said.
North Korea has refused to recognize the so-called Northern Limit Line established following the 1950-53 Korean War and has repeatedly crossed the boundary with ships, and more recently fired artillery near or across it.
The boundary is not clearly marked and the area saw three deadly clashes between the North and South in 1999, 2002 and 2009.
In March, North Korea fired around 500 shells in a live exercise near the sea boundary—around 100 of which fell into South Korean waters. The South responded by firing around 300 shells back across the border.
In 2010, the North torpedoed a South Korean warship in the area and shelled Yeonpyeong island, killing a total of 50 South Koreans.
Tensions on the peninsula have been high for months, amid signs that the North may be preparing to conduct a fourth nuclear test.
Reported by Song Wu for RFA’s Korean Service. Translated by Jung Woo Park. Written in English by Joshua Lipes.