An unidentified North Korean missile is displayed during a military parade past Kim Il-Sung square on July 27, 2013.

Story highlights

North Korean military exercises see shelling into South Korean waters; South responds with artillery fire

North warned South it will conduct military exercises off the country's western coast

North Korea hints at further nuclear tests

Claim comes days after North's test-firing of medium-range missiles into the sea

CNN  — 

A day after raising the possibility of further nuclear tests, North Korea has engaged in provocative live-fire exercises near the South Korean maritime border, leading to an exchange of fire between the two neighbors.

Semi-official South Korean news agency Yonhap reported Monday that the North had begun the drill just after noon (local time). The Joint Chiefs of Staff (JCS) confirmed that some North Korean ordnance landed in South Korean waters, and that the South responded with fire.

The JCS confirmed that the North Korean offshore military exercise began around 12:15 pm (local time) Monday, and said that “a part of North Korea’s shelling reached South Korean side of the NLL and we (South Korea) responded with K-9 self-propelled guns into the North Korean waters above NLL.”

The statement is in line with Yonhap’s report that the North fired “several” artillery shells, to which South Korean military responded with self-propelled artillery fire. The South Korean K-9 howitzers have a 24-mile (40-kilometer) range.

North Korean offshore firing appeared to have resumed after a lull, Yonhap reported, citing a resident of Baekryong Island, which is close to the Northern Limit Line.

Warning fax

The normally reclusive North took the unusual step of informing its neighbor of live-fire drills close in the heavily militarized western sea. Pyongyang sent a fax early Monday demanding that the South “control” its vessels in seven areas of the waterway near the Northern Limit Line.

According to Wee Yong-Sub, a vice spokesman for the South Korean Defense Ministry, the scheduled tests mark the first time – in recent history, at least – that the North has announced live-firing exercises above the maritime border.

“We consider such announcement as a hostile threat and so have activated crisis management operation in case of (military) provocation,” he said. “We stress that we are fully prepared for all situations.”

He added that there are no immediate signs of nuclear tests being carried out by the North.

Nuclear tests

North Korea said Sunday that it “would not rule out” a new nuclear test as it defended its recent mid-range missile launch that triggered international condemnation.

“(We) would not rule out a new form of a nuclear test aimed at strengthening our nuclear deterrence,” Pyongyang’s Foreign Ministry said in a statement carried by the state-run KCNA news agency. “The U.S. had better ponder over this and stop acting rashly.”

The statement did not specify what North Korea meant by a “new form” of test, and Wee said there are no immediate signs of nuclear tests being carried out by the North.

Last week, the Stalinist state launched two medium-range ballistic missiles into the sea off its east coast Wednesday, violating United Nations resolutions that prohibits Pyongyang from conducting such tests.

The U.N. Security Council condemned the move and is considering an “appropriate response,” the council’s president U.N. Ambassador Sylvie Lucas said.

At a briefing Monday, Wee said: “We are fully prepared for all provocation, including North Korea’s additional launching of missiles or nuclear test under the close cooperation with the U.S.”

The military exercises are the latest provocation by the North and come after a maritime dispute last week was seemingly swiftly resolved. On Thursday, a North Korean fishing boat was seized after an alleged incursion into South Korean waters and returned with its three crew members the following day.

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