South Korea blocked North Korean defectors from launching balloons carrying propaganda leaflets over the border after the North threatened military retaliation.
About 80 anti-Pyongyang activists had planned to send 200,000 leaflets by balloons from Imjingak near the Demilitarized Zone at around 11:00 a.m., The Korea Times reported.
However, the military and police banned access to the site, also blocking tourists, residents and journalists from the border region.
North Korea’s army on Friday threatened a "merciless military strike" if the leaflet drop went ahead, an Oct. 19 statement carried by the official Korean Central News Agency said, Bloomberg reported.
It was the first such threat from North Korean since Kim Jong Un succeeded his late father, Kim Jong Il, in December.
Seoul had even prepared to evacuate more than 800 residents from the demilitarized zone if any signs of a possible attack on activists emerged.
However, South Korean troops had not sighted any unusual troop movements north of the border, Bloomberg wrote, citing a Defense Ministry official.
The site would remained sealed off until the activists "give up their plan", an unnamed police official told Agence France-Presse.
"It's for security reasons ... The activists have been blocked from entering the site and will not be able to launch balloons from the park," the official was quoted as saying.
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