South Korea has told its overseas missions to step up security since its embassy in the former Yugoslavia received a threat over Seoul 's crackdown on radical students , the foreign ministry said on Tuesday .
<response> <location>South Korea</location> has told its overseas missions to step up security since its embassy in the former <location>Yugoslavia</location> received a threat over <location>Seoul</location> 's crackdown on radical students , the foreign ministry said on Tuesday . </response>