In what appears to be one of the most serious border incidents since the end of the Korean war in 1953, South Korea says it has returned fire after some 50 North Korean shells landed on the South Korean border island of Yeonpyeong near the tense Yellow Sea border.
Both countries accuse each other of firing first.
At least two soldiers were killed and the clashes prompted Seoul to raise its military alert to its highest non-war level.
Is North Korea taking a calculated risk or is it sending a political message?
Is Beijing likely to stand firm in the face of increased international condemnation and are we heading towards a new Korean conflict?
Joining the programme are Bryan Myers, the director of the Department of International Studies at Dongseo University and the author of The Cleanest Race. How North Koreans See Themselves - And Why it Matters; Paul Chamberlin, a former military attache to South Korea, a fellow at the Center for Strategic and International Studies, and the author of Korea 2010: The Challenges of the new Millennium; and Steve Tsang, a specialist on China and a member of China Centre at Oxford University.
This episode of Inside Story aired on Tuesday, November 24, 2010.