A trash-carrying balloon sent by North Korea landed on the South Korean presidential office compound Wednesday, the Presidential Security Service (PSS) said, reports Yonhap News Agency.

The PSS said it discovered fallen trash on the grounds of the presidential compound while monitoring the latest batch of balloons flown by the North earlier in the day.

"An investigation by the chemical, biological and radiological response team showed the objects did not present a danger or contamination, so they were retrieved," the PSS said. "We are continuing to monitor in cooperation with the Joint Chiefs of Staff."

"It is difficult to handle midair because we do not know what the balloons may contain," a presidential official said. "There will be no change in our policy of collecting them after they have fallen."

The South Korean military has refrained from shooting down the balloons out of concern their contents could spread further and cause more damage.