Tensions between North and South Korea have intensified as North Korea launched another wave of balloons carrying trash, and what is believed to be feces, across the border, targeting its southern neighbor, marking a second wave of such provocations in recent days.

South Korea's Joint Chiefs of Staff (JCS) reported detecting more than 150 balloons since Tuesday night, with many landing in various parts of the country, going as far as South Gyeongsang, an area more than 300 kilometers from the demilitarized zone border between the two countries.

Photos released by the JCS show plastic bags carried by large balloons, with some packages spilling scraps of plastic, sheets of paper, dirt, batteries, shoe parts, and what appears to be feces onto roads and sidewalks.

This move, confirmed by South Korea's military, is a retaliation against South Korean activists who sent anti-North Korea propaganda leaflets, as well as food, medicine, and USB sticks containing South Korean news and entertainment to North Korea.

“Tit-for-tat action will be also taken against frequent scattering of leaflets and other rubbish by [South Korea] near border areas,” North Korea’s vice minister of national defense said on Sunday. “Mounds of wastepaper and filth will soon be scattered over the border areas and the interior of [South Korea] and it will directly experience how much effort is required to remove them.”

The JCS confirmed that the balloons contained "filth and garbage" but no hazardous chemical, biological, or radioactive substances. Government agencies are currently analyzing the contents, and the military is working with the UN Command to address the issue.

Local governments have issued warnings to residents in northern Gyeonggi and Gangwon provinces to avoid outdoor activities and report any suspicious objects to authorities.

“North Korea’s actions clearly violate international law and seriously threaten the safety of our citizens,” stated the JCS. “All responsibility arising from the North Korean balloons lies entirely with North Korea, and we sternly warn North Korea to immediately stop its inhumane and low-level actions.”

Kim Yo Jong, the influential sister of North Korean leader Kim Jong Un, defended the balloon launches, labeling them as a form of "freedom of expression" and “gifts of sincerity,” vowing to send more.

In a statement published by the state-run Korean Central News Agency (KCNA), Kim confirmed that the balloons were filled with toilet paper and other waste materials, intended to mirror the South's long-standing practice of sending anti-North Korean leaflets.

“We have done some of the things they always do, but I do not know why they are making a big deal like they have been hit by a shower of fire,” Kim remarked.

North Korea's disdain for leafleting is not new. In 2020, North Korea demolished a South Korean-built liaison office in a furious response to similar leafleting campaigns. In 2014, North Korea fired at propaganda balloons heading toward its territory, prompting a brief exchange of fire with South Korea.

The South Korean parliament banned leafleting in 2020, restricting the use of loudspeaker propaganda broadcasts and other psychological warfare tactics. Despite the ban, activists like Park Sang-hak of the “Fighters for a Free North Korea” have continued their efforts. Earlier this month, Park's group sent 20 balloons with 300,000 leaflets and 2,000 USB sticks containing K-pop and music videos into North Korea, urging citizens to rise against Kim Jong Un's regime.

North Korea has historically remained isolated from the rest of the world, with strict censorship over incoming information. Foreign materials, including movies and books, are banned, and those caught with contraband face severe punishment. However, in recent decades, North Korea's relationship with China allowed some South Korean cultural elements to seep in.