Replicas of a North Korean Scud-B missile (C-behind) and South Korean Hawk surface-to-air missiles (foreground) are seen at the Korean War Memorial in Seoul on February 17.First of two joint military exercises starts MondayNorth warns it will engulf "Seoul in a sea of flames"Seoul, South Korea (CNN) -- U.S.-South Korean joint military drills kick off Monday, one day after North Korea threatened to engulf Seoul in a "sea of flames." The annual exercises are taking place amid high tensions. North Korea shelled Yeongpyeong Island, killing two South Korean marines and two civilians, last November.
The U.S insists the drills are defensive in nature while training forces to respond to any provocation but North Korea has always denounced them as preparing for an invasion to topple Kim Jong-il's regime.
North Korea's military said Sunday it would retaliate with "an all-out offensive to put an end to the U.S. imperialists' military occupation of South Korea." The military also said the world will see actions "engulfing Seoul in a sea of flames, smashing every move for confrontation." The North often issues such warnings before military drills, but tensions are higher after November's shelling and the March sinking of the South Korean warship, Cheonan, which the South blames on the North.
North Korea also threatened to fire on sites in South Korea where activists and politicians have released balloons carrying propaganda leaflets and DVDs showing anti-government protests across the Middle East and northern Africa. The balloons sometimes carry food and clothes. The North condemned the "psychological warfare" of "clothes, rotten videos and books."
The two drills, Key Resolve, which ends March 10, and Foal Eagle, which finishes at the end of April, will involve 12,300 U.S. forces, many of them coming from units stationed outside Korea. They will also include 200,000 military personnel from South Korea. There are reports of a U.S. aircraft carrier taking part, but neither side has confirmed this.
A U.S. military official told CNN there are no plans for exercises to involve the five frontline islands in the Yellow Sea that are closest to North Korea.