Residents on those front-line islands were asked to go to underground shelters before the drills started, according to an officer at Seoul's Joint Chiefs of Staff, who spoke on condition of anonymity, citing department rules.
Soon after Seoul informed Pyongyang of the training plan Sunday, North Korea's military called the drills a "premeditated military provocation" and warned the South it would retaliate for an attack on its territory. A North Korean officer warned in an interview with the Associated Press in Pyongyang that North Koreans were always ready to "dedicate their blood to defend their inviolable territory."
The drills come two months after the death of late North Korean leader Kim Jong Il His son Kim Jong Un has taken the helm of the nation of 24 million.
The peninsula remains in a technical state of war since the three-year Korean War ended in a truce in 1953.
Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.