A North Korean defectors' group said Friday it has sent more balloons carrying anti-Pyongyang leaflets to North Korea the previous day, after the North warned of counteractions against such a leaflet campaign and Seoul's propaganda loudspeaker broadcasts.

The Fighters for a Free North Koreasaid it sent 20 balloons carrying some 300,000 leaflets, USB sticks and US dollars across the border on Thursday night in the border city of Paju.

The group said the USB sticks contained hit K-drama "Winter Sonata" and songs by popular trot singer Lim Young-woong.

North Korean defector Park Sang-hak, head of the FFNK, earlier warned he will continue to send propaganda leaflets to the North until North Korean leader Kim Jong-un apologizes for the North's sending of trash-carrying balloons to the South.

Inter-Korean tensions heightened after North Korea sent more than 1,000 trash-carrying balloons toward the South in its tit-for-tat action against Seoul activists' leaflet campaigns.

In response, South Korea resumed loudspeaker broadcasts on June 9 for the first time in six years. But it did not turn on the loudspeakers the next day in an apparent bid to prevent the situation from spiraling out of control.

Kim Yo-jong, the powerful sister of North Korean leader Kim Jong-un, earlier warned that her country could take an unspecified "new counteraction" against South Korea if Seoul keeps sending such leaflets and blaring its loudspeaker broadcasts across the border. (Yonhap)