This oughta be interesting...
On Thursday, the South Korea-U.S. combined forces command increased the surveillance to level 2 from the present level 3, Defense Ministry spokesman Won Tae-jae said.*
He said that was the highest level since 2006, when the North conducted its first-ever nuclear test.
The North has long warned it would consider the South's participation in the U.S.-led Proliferation Security Initiative as a declaration of war against North Korea.