SEOUL, South Korea (AP) — South Korea’s military says North Korea is again flying balloons likely carrying trash toward the South, adding to a bizarre psychological warfare campaign amid growing tensions between the war-divided rivals.

South Korea’s Joint Chiefs of Staff said Saturday that the winds could carry the balloons to regions north of the South Korean capital, Seoul. Seoul City Hall and the Gyeonggi provincial government issued text alerts urging citizens to beware of objects dropping from the sky and report to the military or police if they spot any balloons.

There were no immediate reports of injuries or property damage.

North Korea in recent weeks has flown more than 2,000 balloons carrying waste paper, cloth scraps and cigarette butts toward the South in what it has described as a retaliation toward South Korean civilian activists flying anti-Pyongyang propaganda leaflets across the border.

Trash carried by at least one North Korean balloon fell on the South Korean presidential compound late last month, raising worries about the vulnerability of key South Korean facilities. The balloon contained no dangerous material and no one was hurt, South Korea’s presidential security service said.

South Korea, in reaction to the North’s balloon campaign, activated its front-line loudspeakers to blast broadcasts of propaganda messages and K-pop songs. Their tit-for-tat Cold War-style campaigns are inflaming tensions, with the rivals threatening stronger steps and warning of grave consequences.

Animosity between the war-divided Koreas is at its highest in years over the North’s growing nuclear ambitions and the South’s expansion of combined military exercises with the United States and Japan in response to the North's threats.