'S. Korea deployed F-15K during maritime border incident'

The South Korean military deployed a fighter jet when its Navy fired warning shots toward North Korean fishing boats that crossed the maritime boundary, a military source said Friday.

On Friday, South Korean patrol boats fired warning shots toward six North Korean fishing vessels that crossed the so-called Northern Limit Line (NLL) in the latest of a series of incursions in the tensely guarded Yellow Sea. All North Korean boats retreated upon the warning shots.

"When the Navy fired warning shots, a joint force was standing ready and an F-15K fighter jet was deployed as part of the force," the source, said asking for anonymity as he is not allowed to talk about military information. "If North Korea's military launches provocations near the NLL, we will operate the joint forces to promptly and sternly respond."

The F-15K fighter was equipped with air-to-surface and air-to-air missiles, the source noted.

The NLL, the de-facto maritime boundary between the two Koreas, has been the scene of several bloody skirmishes between the navies of the two Koreas. Most recently, tensions escalated after Pyongyang torpedoed a South Korean warship in March 2010 and shelled Yeonpyeong Island eight months later, killing 50 South Koreans in that year.

It was the first time in two years that Seoul resorted to firing warning shots to push North Korean fishing boats back. About 100 North Korean boats and 300 Chinese ships are currently fishing for crabs in waters north of the NLL in the peak crab season, according to officials.

Tensions have escalated since early Friday, when the Joint Chiefs of Staff said it raised the alert status near the western sea border and vowed to sternly respond if the border crossings continued.

Seoul and Washington have subsequently allocated more intelligence gathering assets to check for any changes in the North's armed forces to forestall any provocations, according to defense officials.

Pyongyang does not recognize the NLL, arguing it was unilaterally drawn by the U.S.-led United Nations forces at the conclusion of the 1950-53 Korean War that ended in a truce. It has demanded that a new border be drawn farther south. (Yonhap)