Concern over possible North Korea missile test
15 April 2013 Last updated at 09:53 BST
There is growing concern that North Korea may carry out a missile test in the next 24 hours to coincide with ceremonies marking the birth of its late founder, Kim Il-sung.
Last week Japan deployed missile-defence systems in its capital as the North warned foreigners in the South to take evacuation measures in case of war.
The BBC's World Affairs Correspondent, John Sudworth, is in South Korea, on the border with the North.