(LONDON and SEOUL) — Refuse carried by a North Korean “trash balloon” landed inside the South Korean presidential compound in the capital city of Seoul on Thursday amid rising tensions between the two neighbors.

The South Korean Presidential Security Service “identified trash that blew up in the air and fell in the office compound early this morning,” the service said in a Thursday statement.

“After a safety inspection, the service collected the fallen objects after confirming they do not contain danger or contagiousness,” the service added. “The service is monitoring the situation in cooperation with the Joint Chiefs of Staff.”

This is the second time one of North Korea’s trash balloons fell inside the South Korean Presidential Office Compound.

Cross-border balloons have been one element of the recent deterioration in inter-Korean relations, with the period of diplomatic thaw from 2017 giving way to new tensions since the election of conservative South Korean President Yoon Suk-yeol in the spring of 2022.

The balloons have been found carrying household waste items including paper, vinyl and plastic bottles, according to the South Korean military. Some trash balloons carried manure.

Several fires have also been reported in metropolitan areas attributed to “heat timers” attached to the balloons.

North Korea launched a total of 5,500 trash balloons at South Korea on 22 occasions from May 28 to Sept. 23 this year, Lee Sung-joon — a spokesperson for South Korea’s Joint Chiefs of Staff — said last month.

Seoul estimated that North Korea spent 550 million won — around $411,600 — to produce the balloons, South Korea’s Yonhap news agency reported.

Lee said in September after 120 balloons were launched that Seoul would consider military action to down them if necessary. “If North Korea’s continued trash balloons are judged to pose a serious threat to the safety of our citizens or to have crossed the line, the military will take stern military action,” he said.

South Korean civic groups have also launched balloons across the border, much to Pyongyang’s chagrin.

Such balloons often carry rice, essential medicine and leaflets critical of leader Kim Jong Un’s regime. North Korea has repeatedly protested such action and threatened a response.

The frontier region has been particularly tense this month. On Oct. 15, Seoul said North Korea blew up two border roads and deployed “heavy equipment” for “further operations.”

South Korean troops along the border fired warning shots in response, the South Korean Joint Chiefs of Staff said in a statement.

The detonations followed a North Korean warning that it intended to permanently seal off border access routes, cutting rail and road connections and reinforcing defensive fortifications.

The explosions came shortly after Kim ordered his artillery forces — traditionally the most potent threat to the capital Seoul, which sits around 35 miles from the frontier — onto full alert, having accused Seoul of flying drones over Pyongyang.

The face-off on the Korean Peninsula may now spread to Ukraine, where Seoul, Kyiv and Washington, D.C. have accused Pyongyang of deploying troops in support of Russia’s invasion.

Yonhap reported that Seoul is now considering sending weapons to Ukraine in response, having so far only provided humanitarian aid.

Yonhap also said South Korea is considering sending military and intelligence personnel to Ukraine to probe North Korean battlefield performance and help with interrogations of captured North Korean fighters.

ABC News’ Ellie Kaufman contributed to this report.

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