North Korean defectors in the South launched 200,000 anti-Pyongyang leaflets across the tense inter-Korean border on Saturday, the birth anniversary of the North's late leader Kim Jong-Il.
The defectors used gas-filled balloons to float the leaflets along with $1 currency notes across the western border town of Imjingak, despite high tensions owing to the North's third nuclear test on Tuesday.
The balloons were inscribed with slogans such as "Stop provocative acts with missiles and nuclear tests", "North Koreans rise up" and "The Kim dynasty will soon collapse".
North Korea celebrates the birthdays of both late leaders -- Kim Jong-Il's on February 16 and his father Kim Il-Sung's on April 15 -- as major national holidays.
Kim Jong-Il, who died of heart attack in December 2011, was succeeded by his son Jong-Un.
Anti-Pyongyang activists momentarily suspended such leaflet launches until after the South's presidential election in December as the government urged them to halt such activities for fear of provoking Pyongyang.
North Korea has in the past threatened "merciless military strike" in response to anti-regime propaganda leaflets, with local residents warned to evacuate such areas.
The North conducted a third nuclear test on Tuesday, whose detonation power was much larger than those of two previous ones in 2006 and 2009.
Pyongyang said the test was a riposte to UN sanctions imposed after its launch of a long-range rocket in December, which it claimed was part of a legitimate space programme.