Some of the trash balloons that North Korea has launched over the border since last month carried parasites from likely human feces and other excrement, as well as dirty underwear, socks and other clothes, Seoul’s unification ministry has concluded.

The ministry’s announcement of the results of a weekslong investigation marks the first time the government has officially acknowledged the possibility that the balloons carried human feces, amid concerns about the threat that they pose to public health.

“Analysis by specialized agencies revealed the presence of numerous parasites such as roundworms, whipworms and threadworms in the soil contained in the filth,”