South Korean soldiers of an artillery unit take part in a drill with 105mm Howitzers, near the demilitarized...
South Korean soldiers of an artillery unit take part in a drill with 105mm Howitzers, near the demilitarized zone separating the two Koreas, in Paju, north of Seoul, April 17, 2013. North Korea issued new threats against South Korea on Tuesday, vowing "sledge-hammer blows" of retaliation if South Korea did not apologize for anti-North Korean protests the previous day when the North was celebrating the birth of its founding leader. REUTERS/Kim Hong-Ji (SOUTH KOREA - Tags: POLITICS MILITARY)