There is speculation that North Korea could launch a missile today - perhaps aimed at Japan.
Talking to senior diplomats there is a sense is that if the missile trajectory shows it will land harmlessly in sea then it won't be shot down
Through her tears, a North Korean woman told me how she had to escape: risk death while running across the border or die of starvation.
Memories of the Korean war are never far away in South Korea, where residents have grown used to living with the constant threat of war.
North Korea said it will withdraw workers from the Kaesong factory park run jointly with South Korea and suspend all operations there.