Two North Korean patrol boats crossed into South Korean territorial waters late on Saturday but retreated after receiving warnings from the South Korean Navy, the Yonhap news agency said on Sunday.
Yonhap cited reports by S. Korea's Joint Chiefs of Staff saying that both boats crossed the Northern Limit Line (NLL) in the Yellow Sea in the course of one hour and came about 2.2 kilometers (1.3 miles) into South Korean waters.
The first boat retreated after a warning communication, while the second boat was forced to flee by two warning shots fired by a South Korean warship, the agency said.
Seoul suspects Pyongyang of sinking a South Korean warship near the NLL in March and may issue an official statement, based on the results of an investigation, later in May.
The NLL was unilaterally drawn by the U.S.-led United Nations Command in the wake of the 1950-1953 Korean War and has been a sticking point between the North and the South.
Pyongyang has not acknowledged the borderline and has drawn a new one on its own south of the current border. Naval clashes between the two states over the disputed area took place in 1999, 2002 and last year.
The two countries remain technically at war as their conflict ended only in an armistice in 1953.
MOSCOW, May 16 (RIA Novosti)
