South Koreans launched 100,000 anti-Kim Jong-un propaganda leaflets over the border into North Korea on Monday.

AFP said the activist group, Fighters for Free North Korea, had sent 50,000 similar leaflets over in an earlier exercise on Saturday, on the sixth anniversary of the sinking of South Korean warship, the ROKS Cheonan, which the South blames the North for.

Longstanding strategy: People tying propaganda-filled balloons in 2008. Image: AP

Image: lee jin-man/AP

The leaflets were floated over attached to gas-filled balloons, and criticised the North's nuclear weapons programme and its missile tests.

These leaflets have been effective in angering Pyongyang in the past, which last month launched its own revenge floating packages — balloons filled with refuse like used toilet paper and cigarette butts.

The South Korean group plans to continue with its plans to float 10 million of these leaflets over the next three months.

2011 photo of people launching balloons criticising the former leader, Kim Jong-Il. Image: ASSOCIATED PRESS

Image: lee jin-man/AP

The activity comes on the backdrop of heightened tensions between North Korea and its main enemies, the U.S., South Korea and Japan. The North has threatened nuclear action against them, while it boasts about ongoing progress in its weapons technology.

On Saturday, the reclusive state released a dramatic propaganda video of it obliterating Washington with a nuclear missile.

A South Korean conservative activist releases balloons on the eve of the anniversary of the sunken ship in 2015. Image: Ahn Young-joon/AP

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