The United States is closely monitoring South Korea’s criminal investigation of three human rights groups known for sending materials like bibles and USB sticks into North Korea, the U.S. State Department told NK News on Friday.

Cases focusing on nine individuals from these groups were sent to the prosecutor’s office, Seoul’s Metropolitan Police Agency confirmed on Thursday  — a decision that drew criticism from some in the human rights community for representing censorship that favored North Korea.

Joshua Stanton, a fellow at the Institute for Corean-American Studies and head of the One Free Koreablog, also condemned the