Tensions between North Korea and South Korea came to a head once again on Tuesday as the two nations exchanged deadly rounds of artillery fire. The shooting lasted for about an hour, killing two South Korean marines and two civilians on the country's Yeonpyeong Island--located in the Yellow Sea.

Both nations blame the other for starting the conflict. North Korea contests that South Korea fired first, while South Korea says its shots were part of a scheduled military exercise performed every year. The United States, an ally of South Korea, condemned the deadly North Korean attacks.

The deadly exchange is the latest in a recent string of conflicts between the two nations. In March an investigation unveiled that a North Korean torpedo sunk a South Korean ship, killing 46 sailors. And in August, the North Koreans set-off artillery shells into an area of the Yellow Sea where South Korean Navy had just wrapped up live exercises.

It's a reminder that the two nations are technically still at war, some 57 years after the Korean War armistice. The armistice called for a cease fire and created a demarcation line--on land and sea--between North and South Korea. However, North Korea to this day disputes the maritime (sea) border, contending its territorial waters expand further to the south.

"I thought the South Korean military was carrying out a heavy artillery exercise. When the bomb went off near my house, which collapsed, I realized it was North Korea who had fired. I thought I would die if I left the house." --Lee Chun-Ok, a resident of Yeonpyeong Island

"The U.S. strongly condemns this aggression on the part of North Korea. And we stand firmly with our allies." --Stephen Bosworth, U.S. Special Representative for North Korea Policy

1. Where is Asia? What countries are in Asia?

2. Why are there two Koreas: North Korea and South Korea?

3. How do wars end? How do you know when a war is really over?

1. If these small conflicts between North Korea and South Korea continue, what do you suppose might be the end result?

2. How could this latest conflict between North Korea and South Korea be resolved?

3. Have you ever been in a conflict with a person or a group? What was the eventual outcome of that conflict?

4. Read this story on the government in North Korea [ http://www.pbs.org/newshour/extra/features/world/july-dec10/korea_10-05.html ]

5. How might this transfer of leadership affect the military's behavior?