(Seoul) North Korea is once again sending balloons likely to transport waste to its southern neighbor, the Seoul army said late Monday, thus continuing the balloon war between the two Koreas.

Seoul’s Joint Chiefs of Staff said the North is “launching garbage balloons towards the South again,” adding that the balloons are currently floating across the border.  

“Citizens are advised to be careful of falling debris. If you find balloons on the ground, do not touch them and report them to the nearest military unit or police station,” according to the statement.  

Seoul city authorities issued an alert to residents on Monday evening.

North Korea is thus acting in retaliation for the dissemination of propaganda, in particular by leaflets or USB sticks, against the North Korean regime by human rights activists from South Korean territory.

The North is extremely sensitive to its people’s access to South Korean pop culture. A United Nations report even indicates that possession of large quantities of this type of content is punishable by death.  

Kim Jong-un received Russian leader Vladimir Putin last week and signed a mutual defense agreement that sparked outrage in Seoul. In response, the south, a major arms exporter, said it would “reconsider” a long-standing policy that prevented it from supplying arms directly to Ukraine.  

Experts said it was possible border tensions could escalate quickly. “We also cannot rule out the possibility that North Korea will take provocative, more radical steps due to the trust it gained after signing the treaty with Russia,” said Hong Min, senior researcher at the Korea Institute for National Unification.