North Korea said it would stop sending trash-filled balloons over the border to South Korea but vowed to resume such acts if anti-North Korean leaflets are flown over again by activists in the South.

In a statement carried by the North’s state-run Korean Central News Agency(KCNA) on Sunday, North Korean vice defense minister Kim Kang-il said the country would temporarily halt dropping trash over the border, claiming they sent a total of 15 tons of trash to its neighbor using 35-hundred balloons between last Tuesday night and Sunday morning.

Kim said the North let South Koreans experience enough of how unpleasant it feels and how much effort it takes to collect the trash. 

The North Korean official said the balloons were “strictly a responsive act” to anti-North Korea leaflets sent from South Korea.

He then warned that if South Korean activists float anti-Pyongyang propaganda leaflets via balloons again, North Korea will resume flying its own balloons to dump rubbish hundreds of times the amount of the South Korean leaflets found in the North.

South Korea’s Joint Chiefs of Staff said that some 720 balloons flown from the North were discovered in various parts of the country as of 1 p.m. Sunday, in addition to about 260 balloons found three days earlier.