North Korea has allegedly sent approximately 260 balloons carrying rubbish and faeces into South Korea in retaliation for anti-Pyongyang leaflets floated across the border by South Korean activists. The event reportedly began on Tuesday night and occurred after North Korean defense vice-minister, Kim Kang-il, warned of retaliatory measures.

The South Korean Joint Chiefs of Staff (JCS) announced on Wednesday that the balloons carried trash, including plastic bottles, batteries, and filth, advising residents to avoid contact and report findings to authorities. Some balloons reached as far as southeastern South Korea.

The North Korean action led South Korea’s JCS to state that these acts violate international law and pose a threat to citizen safety. The JCS, along with government ministries and police, is working to collect and clean up the waste.

North Korea communicated that it was responding to what it perceived as provocations from the South, stating it will take immediate action when its sovereignty is violated. The conflict stems from long-standing tensions, worsened by the balloons carrying propaganda that South Korean activists have sent to the North for years.