Two South Korean pastors are currently being detained in North Korea on charges of espionage.

The Korean Central News Agency (KCNA) announced in a press conference on 27 March that North Korean security officials arrested Kim Kuk Gi and Choe Chun Gil for allegedly spying on the communist state on behalf of the South Korean National Intelligence Service (NIS), Christianity Daily reports.

"They zealously took part in the anti-DPRK smear campaign of the US imperialists and the puppet group of traitors to isolate and blockade the DPRK in [the] international arena by labeling it 'a country printing counterfeit notes' and 'sponsor of terrorism' while pulling it up over its 'human rights issue,'" the KCNA alleged.

According to Reuters, North Korean media accused one of the pastors of setting up an underground church in Dandong, China and of "illegally spreading foreign information on USB sticks and SD memory cards."

An official within the South Korean NIS told Reuters that the accusations against the two men are "groundless."

Reuters also said that the two men's nationalities were confirmed by the South Korean Unification Ministry, responsible for handling relations between the two Koreas, which did not comment on their backgrounds. 

According to Voice of America, a source within the General Assembly of Presbyterian Church in South Korea revealed that Pastor Kim was doing missionary work in Dandong among North Korean defectors. The source, who spoke on condition of anonymity, said he lost contact Pastor Kim around two years ago.

Christianity Daily also reported that a contact within China said that Pastor Kim was requested to report to Pyongyang December of last year.

The Presbyterian Church condemned Pastor Kim's arrest.

"In treating Kim in this way, North Korea is directly violating international customs as well as the basic worth and human rights of people," Christianity Daily quoted the Church as saying.

The South Korean government has demanded the release of the two men.