South Korea's military has warned people to avoid touching the balloons and report them to authorities.

North Korea is sending more balloons carrying rubbish across the heavily fortified southern border, South Korea’s military has said.

It comes just days after North Korea appeared to send at least 200 balloons carrying rubbish over the border in retaliation for propaganda leaflets sent from the south.

South Korea’s defence minister Shin Won-sik called it “unimaginably petty and low-grade behaviour” while the military added it is examining the contents of the bags floated over the border by the balloons.