A Seoul-based North Korean defectors' group on Monday said it would send more leaflets and digital copies of popular South Korean songs across the border in a growing cross-border tit-for-tat that most recently saw Pyongyang send balloons loaded with waste to the South.

North Korea sent hundreds of balloons last week, threatening to send more if balloons carrying South Korean leaflets entered its territory again.

The civic group Fighters for a Free North Korea revealed its plans to respond by sending 200,000 leaflets and 5,000 USB drives containing Korean dramas and songs of Lim Young-woong, a popular South Korean singer.

"(North Korean leader) Kim Jong-un sent South Korean people garbage, but us defectors will send love and truth to our compatriots up north," said Park Sang-hak, the leader of the group who defected from the hermit kingdom in 1998.

The group plans to start sending the leaflets and the USB drives on Thursday, which is the South Korean Memorial Day.

Last week, North Korea sent a large number of balloons carrying trash and animal feces.

Pyongyang on Sunday said it would stop sending the trash-filled balloons across the border, but said it would resume the operations if Seoul sends any more of the leaflets carrying negative messages toward the Kim regime.

The defector group called the recent move by North Korea as "an embarrassing form of threat and blackmail," and said it will consider not sending the leaflets if Kim apologizes for the garbage balloons.

The anti-North leaflets sent by the Fighters for a Free North Korea have been the subject of dispute here.

In October 2014, Park's group sent a balloon full of leaflets toward the North from a border area in Paju, some 40 kilometers northwest of Seoul. North Korean soldiers responded by shooting the balloons, which then was followed by South Korean military shooting in response. No damage was reported on either side.

Two weeks later, the defector group arrived at the same site to send more leaflets Northward, a move that infuriated Paju residents who complained that the leaflets are endangering their livelihood.

After the Moon Jae-in administration took office in 2017, it banned the release of balloons, a move unpopular with some conservatives that was ruled unconstitutional last year.

Thae Yong-ho -- a South Korean lawmaker who defected from the North in 2017 -- said in a past interview that he personally opposes "some organizations" publicly sending the leaflets, saying such operations should be conducted discreetly.