The South Korean Navy on Thursday kicked off a three-day maritime exercise to defend the western sea border from possible North Korean provocations, the military said.
The exercise came as North Korean fishing and patrol boats often show up near the western maritime border, widely known as the Northern Limit Line (NLL), in June, the peak season for catching blue crabs.
The maritime drill is being conducted amid the possibility that North Korea could provoke a maritime confrontation. The two Koreas fought several bloody sea battles along the NLL in 1999, 2002 and 2009.
Pyongyang does not acknowledge the de facto demarcation line drawn unilaterally by the U.S.-led United Nations Command when the 1950-53 Korean War ended in a cease-fire.
"About 200 North Korean fishing vessels are operating in waters near the NLL," said a military official, adding that the figure is 1.7 times higher than last year.
The drill will involve around 20 warships including the 7,600 ton Aegis-equipped destroyer and other military assets such as the P-3 surveillance plane and Lynx antisubmarine helicopters, according to military officials.
"We are keeping full combat readiness to swiftly respond to the enemy's possible provocations in waters off the west coast," the Navy said in a statement.
During the peak season for crab fishing, Chinese fishing boats often cross into South Korean waters in the Yellow Sea in search of bigger hauls, regularly leading to crackdowns by the South Korean Coast Guard.
Chinese fishermen are presumed to have bought the right to operate in waters on the North Korean side of the border, but they often intruded into the South Korean side.
North Korea has recently raised its combat readiness near the western sea border, according to South Korean military officials.
The communist country is known to have constructed a naval base capable of accommodating about 70 air-cushioned vessels in Goampo, some 60 kilometers north of the NLL.
Early this year, the North built a 20-meter-high steel tower on Ari Island, an uninhabited piece of land, some 12 kilometers north of frontline Yeonpyeong Island and put a monitoring device on it.
Reflecting the tense nature of the NLL and the need for Seoul to stay on guard, North Korea torpedoed a South Korean warship in early 2010, killing 46 sailors, and also shelled Yeonpyeong Island near the demarcation line in November of that year. (Yonhap)