Kim was killed at an airport in Kuala Lumpur on Feb. 13 by two Asian women, who allegedly smeared the banned chemical weapon VX nerve agent on his face.

Malaysian police said that eight North Koreans are suspected of being involved in the killing. North Korea claimed that Malaysia colluded with South Korea to manipulate the probe.

"We will inform North Koreans of the act of brutality conducted by Kim Jong-un," said Park Sang-hak, a defector who leads the group.

Along with the leaflets, the civic group said it also sent 2,000 one-dollar bills, 300 booklets, 500 USBs and 500 micro SD cards.

It regularly launches large balloons carrying such anti-Pyongyang information in a campaign to spread dissenting messages in the reclusive regime.

The group plans to send some 10 million leaflets over the border this year, starting with the latest event.

Also on Tuesday, some 6,000 North Korean propaganda leaflets were found in Incheon, west of Seoul.

They carried messages glorifying Kim Jong-un and criticizing the annual joint Key Resolve exercise between South Korea and the United States.

The allies ended their two-week computer-based war game on Friday. Separately, the joint two-month Foal Eagle combat training exercise that kicked off on March 1 is still under way. (Yonhap)