The attack took place at the heavily populated Yeonpyeong island.
Following the attack on Monday, Nov 29, S Korean president Lee Myung-bak in a nationally televised statement said, "If the North commits any additional provocations against the South, we will make sure that it pays a costly price without fail."
Japan's Prime Minister Nato Kan condemned N Korea's inhuman act and articulated, "Japan would ally with S Korea and United states to counter North Korea's reckless and outrageous acts."
Amid heightened tension following the US state department documents leak on Sunday, Nov 28, a possible scenario for discussions between US and S Korea over possible reunification of the peninsula was set forth. Also, the America worry over Pyoygyang's nuclear weapons programme is looming large.
The documents leaked by online whistle-blower WikiLeaks depicted, the deep US worries about N Korea and Iranian nuclear programs.
The New York Times published documents that indicated that United States and South Korea were "gaming out an eventual collapse of North Korea".
After winding up his speech, Lee reinstated his threat from N Korea to attack South Korea and the United States, calling the allies' joint war drills "yet another grave military provocation."