The researchers say larger class sizes are another possible reason for the increase in injuries.

VOA: special.2009.08.06

Investigators say they are looking at every possible reason for the shooting.

VOA: special.2009.11.14

Hyun adds,the North Korean leader also has to think about possible power succession, whether it happens right away or some time later- that is another reason to reinforce his power base.

VOA: standard.2009.06.22