... with a likely request for reenforcing American and South Korean troops around Seoul.

South Korea's Joint Chiefs of Staff (JCS) on Monday placed all military units on emergency alert following the news of North Korean leader Kim Jong-il's death.
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Officials said they may raise the "Defcon," a five-stage combat alert level, from its current level of four to three, and may also increase the Watchcon, an anti-North Korea surveillance alert, from three to two. Watchcon two signifies a state of emergency with indications of a vital threat from North Korea.

The South last raised its Watchcon to two immediately after the North shelled Yeonpyeong Island, just south of the Yellow Sea border on Nov. 23, killing two marines and two civilians.

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According to the JCS, the Master Control and Report Center (MCRC) at Osan Air Base, south of Seoul, which handles aerial monitoring and analysis, plans to ask for reinforcement by both South Korean and U.S. forces.

Promising negotiations between the United States and North Korea—towards a peace treaty—are now on hold.