South Korea on Thursday warned North Korea it would immediately fire back if the North makes provocations into the South.
"In the case that North Korea's bullets or artillery fall into our military guard posts, our soldiers and military commanders would launch an immediate response without having to seek approval from the defense minister or the chairman of the Joint Chiefs of Staff," South Korean Defense Ministry spokesman, Kim Min Seok, said during a press briefing.
Kim's comment was made in response to a North Korean statement released earlier Thursday, in which the North accused the United States and South Korea of planning joint military drills, known as Ulji Freedom Guardian, from Monday.
North Korea is "no longer what it used to be in the 1950s," a spokesman for North Korea's Foreign Ministry said in the statement, reported by the North's Korean Central News Agency. "It has strong military muscle to cope with any mode of war desired by the U.S.," it said.
South Korea and the United States have said their joint drills are entirely defensive in nature, but North Korea claimed they were a rehearsal for an invasion of the North.
Tensions between the two Koreas have heightened recently after South Korea accused North Korea earlier this week of placing landmines in the demilitarized zone and seriously injuring two South Korean soldiers.