South Korean troops fired warnings shots Monday after a North Korean patrol approached the tensely guarded land border that separates the rival countries, the Joint Chiefs of Staff (JCS) said Monday.

However, there was no exchange of fire as the North Korean patrol moved away from the military demarcation line (MDL) without firing back, according to the JCS.

"Some 10 North Korean soldiers came close to the military demarcation line (MDL) in the northern city of Paju at around 9:40 a.m. today," a JCS officer told reporters. "They were taking pictures of the signposts set up there to mark the demilitarized zone." 

The North Korean soldiers came short of crossing the border into the South, but South Korean troops fired a dozen rounds of warning shots, he added.

"The soldiers completely retreated some three hours later, and no other unusual movements have been detected since," the officer said.

The incident took place when the South kicked off the two-week annual Hoguk drills scrambling all branches of service aimed at boosting joint capabilities against North Korea's possible provocations.

Last month, South and North Korea exchanged fire after troops from the communist country drew near the MDL in Paju. No casualties were reported.

"Pyongyang appears to have carried out such provocative acts to test our preparedness and to heighten tensions to have the upper hand in inter-Korean relations," a defense ministry official said, requesting anonymity. (Yonhap)