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South Korea on edge, warns North of strike if it is attacked again

SEOUL — South Korea’s military warned Wednesday that it would respond to any attack from North Korea with “strong and stern measures” against Pyongyang’s top leadership, in a particularly vivid threat coming after the North vowed to nullify an armistice agreement ending the Korean War.

The tit-for-tat threats could prove to be mere bluster, analysts said. But the rhetoric sets up an especially tense period on the Korean Peninsula, with the US and South Korean militaries set to carry out joint training drills that the North considers a “dangerous nuclear war” maneuver, and with the UN Security Council deliberating new sanctions to limit Pyongyang’s weapons program.

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The North said Tuesday that it will “completely declare invalid” the armistice on March 11, the day those joint drills enter the “full-dress stage.” The United States and South Korea began a two-month series of war exercises March 1, but an additional set of exercises — the Key Resolve drills, involving 10,000 South Korean and 3,500 US troops — kicks off Monday.

The joint drills are an annual event, as are the North’s denunciations of them. But the South’s rare warning Wednesday highlights how leaders here are increasingly on guard over their militant neighbor, which is emboldened by an improving nuclear and missile program, guided by a relatively unknown leader, and prevented from backing down because of its own posturing.

South Korea typically shrugs off the rhetoric from North ­Korea, but Wednesday its Joint Chiefs of Staff released a statement saying the South would respond to provocations by striking “not only at the origin of provocation [and at] supporters of the provocation but also the top operatives.”

North Korea hit the South in two fatal attacks in 2010 and South Korea promised to strike decisively if attacked again.

North Korea has started submarine drills before nationwide military drills begin next week, South Korea’s Yonhap news agency reported.

In its statement Tuesday, the North threatened to cut off a hotline at the demilitarized zone and blasted the United States and South Korea for their effort to “slap” tougher sanctions.

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