A group of South Korean activists released balloons carrying anti-North Korean leaflets across the border Sunday, brushing aside warnings of retaliation from the North.

In an unusual letter sent recently to the presidential office Cheong Wa Dae, the North called on the South Korean government to stop local activists from sending such anti-Pyongyang leaflets across the border and alluded to retaliation against the senders.

Defying the warning, 10 activists from Fighters for Free North Korea launched 10 big balloons carrying 200,000 anti-North Korea leaflets into the sky in Paju, north of Seoul.

The waterproof leaflets contain messages denouncing the three-generation power transfer in the North as well as the dire economic situation, while praising South Korea's economic prosperity.

Some South Korean activists, mostly defectors from North Korea, often float balloons carrying such leaflets near the inter-Korean border to denounce and publicize the dire political situation of the North.

"In spite of any threat or warning from the North, we will continue sending letters of truth until the North Korean people achieve liberalization," the activist group's chief, Park Sang-hak, said during the leaflet campaign.

The controversial campaign also drew a group of opposing activists to the border town, who called for a suspension of the practice.

"Sending anti-Pyongyang leaflets constitutes a dangerous act that devastates peace on the peninsula," said an activist from the Korea Alliance of Progressive Movements.

The government has long maintained that it has no legal basis to stop civic groups' leaflet activities. It has recently said that "The anti-Pyongyang leaflet issue is something private activists have to decide for themselves." (Yonhap)