Activists have recently floated balloons carrying 200,000 propaganda leaflets across the border into North Korea.

Park Sang-hak of Fighters for Free North Korea said on Monday that 10 balloon were floated from Paju, Gyeonggi Province across the inter-Korean border carrying the leaflets denouncing Kim Jong-un's dictatorship and the regime's threat of missile and nuclear tests.

With the leaflets activists also sent 1,000 US$1 bills, 500 DVDs showing President Park Geun-hye's China visit and the North Korean regime's human rights abuses, and 500 USB memory sticks.

"We'd earlier prepared to send these leaflets around Sept. 5, but decided to delay the plan for a while as inter-Korean relations improved," Park said. "But we decided to send them anyway because of the North's recent threat to tests missiles and nuclear weapons."

The two Koreas earlier this month agreed to hold another round of reunions separated by the Korean War in late October.