The United Nations Command(UNC) has launched an investigation into North Korea’s sending of balloons carrying garbage and excrement across the inter-Korean border on Tuesday night. 

The U.S-led multinational command said in a Facebook post on Wednesday that it is conducting a formal investigation into the matter, which the Neutral Nations Supervisory Commission will observe to provide third party oversight. 

The UNC, which monitors compliance with the Armistice Agreement that halted the Korean War, said it is working to confirm the details of the incident via its special investigation.

The UNC said the military action of deploying mass numbers of balloons with substances such as fecal matter and other contaminants that can cause harm to local populations is not only offensive and unsanitary but constitutes a violation of the Armistice Agreement. 

UNC spokesperson Mayra Nanez said that North Korea has repeatedly stated its desire to be treated as a responsible member of the international community, but the act of sending balloons containing fecal matter and other contaminants into a neighbor’s airspace and affecting its populace is irresponsible. 

The spokesperson condemned any violations of international law that disrupt efforts to preserve peace on the Korean Peninsula.