S. Korea hopeful, on "high alert" with Kim gone

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South Koreans read headlines about Kim Jong Il's passing
Pedestrians read a special edition a South Korean newspaper announcing the death of North Korean leader Kim Jong-Il, in Seoul on December 19, 2011.
This story was filed by CBS News' Audrey Yoo

(CBS) SEOUL - There were mixed feelings Monday in South Korea, as the nation absorbed the news of North Korean leader Kim Jong Il's death.

South Korean government offices, diplomatic missions, and all military units were immediately put on "high alert," and monitoring across the border was been stepped-up.

In Seoul, South Korean President Lee Myung-bak held an emergency national security meeting with his cabinet.

"Peace and stability on the Korean Peninsula should not be threatened by this incident," said Lee. "We should make thorough preparations to maintain peace and stability on the peninsula and should continue close cooperation with the international community."