North Korea has sent more than 150 balloons carrying trash across the inter-Korean border, Seoul's military said Wednesday, after the North warned of "tit-for-tat action" against anti-Pyongyang leaflets flown by the South's activists. Since Tuesday night, the balloons have crossed the border to fall in various locations across the country, reaching as far as the southeastern province of South Gyeongsang, and scatter waste as they fell to the ground, according to the Joint Chiefs of Staff (JCS). The fallen balloons appeared to have carried various pieces of trash, such as plastic bottles, batteries, shoe parts and even manure, a JCS official said, with military officials collecting the objects for a detailed analysis. "These acts by North Korea clearly violate international law and seriously threaten our people's safety," the JCS said. "(We) sternly warn North Korea to immediately stop its inhumane and vulgar act." On Sunday, North Korea said it will scatter "mounds of wastepaper and filth" over the border ar...