The North Korean army vowed Friday to launch a "merciless military strike" if activists in the South go ahead with plans to scatter propaganda leaflets from balloons floated over the border next week. "The moment a minor movement for the scattering is captured... a merciless military strike by the Western Front will be put into practice without warning," the Korean People's Army said in a statement. The statement, carried on the official Korean Central News Agency, warned residents in the area where the activists plan to launch their balloons to "evacuate in anticipation of possible damage".