- author, Annabel Liang
- role, BBC News
Officials said a balloon loaded with garbage sent by North Korea landed at the South Korean presidential palace in Seoul.
This is the first time that the office of South Korea's top leader, which is designated a no-fly zone, has been hit by balloons launched from Pyongyang.
The Presidential Security Service said a chemical, biological and radiological warfare response team had been dispatched to retrieve the balloon.
No contamination or safety risks were found.
Local news site Yonhap News reported that the military decided not to shoot down the balloons for fear that their contents would spread further.
Balloons have also landed in other parts of Seoul, with authorities urging residents to avoid touching the balloons and to “report any incidents to the nearest military unit or police station.”
South Korea's Joint Chiefs of Staff told Reuters that winds were blowing from the west, meaning any balloons sent towards South Korea were likely to land in Gyeonggi province in the country's most populous north and home to the capital.
The latest incident came days after South Korea's military responded to an escalation of missile launches by resuming propaganda broadcasts from loudspeakers along the border.
North and South Korea have used balloons in propaganda operations since the Korean War in the 1950s.
Launches have become more frequent this year, with thousands of balloons being launched across the border from North Korea since May.
North Korea said Wednesday's balloon launch, its 10th this year, was in retaliation for balloons sent by South Korean activists.
The items were said to include anti-Pyongyang leaflets, as well as food, medicine, cash and USB sticks containing K-pop videos and dramas.