state. >> narrator: like jeong, yong hee says she suffered at the hands of the north korean regime. her brother was caught trying to defect and she was punished. she says she was locked up and tortured by security agents. >> narrator: she says the officers tied her brother's hands to the back of a truck and dragged him along a dirt road as an example to others. >> narrator: yong hee escaped with her husband and son, leaving her brother and mother behind. (train whistle blowing) (explosion) >> sharp new warning of all-out war. for the first time, the mysterious and secretive nation... >> there is nothing imminent, but these threatening statements have everyone on edge. >> are we on the brink of a nuclear war? >> narrator: last spring, north korea became the first country since the cold war to threaten the united states mainland with a nuclear attack. >> when watching this i thought, wow, even from north korean standards, this is really over the top. they always do this cycle of provocation. it's just the intensity of the recent provocation was even greater. >> i don't think anybody r