A US citizen sentenced to 15 years of hard labor in the Democratic People's Republic of Korea was a missionary who used his tourism business to form groups to overthrow the government, the DPRK's Supreme Court said.
Kenneth Bae, 44, was sentenced earlier this month after being detained late last year while leading a tour group in Rason.
"In order to carry out the plan, he infiltrated at least 250 students who had been educated at the plot-breeding bases operated by him into Rason City disguised as tourists," a court spokesman told KCNA news agency in a report issued early on Friday.
Bae has acknowledged being a missionary and said he conducted services in the DPRK, according to an audio sermon and note posted on the website of a Korean Presbyterian church in St Louis in the United States.
Recordings on the church's website showed him talking about a trip to Rason in 2011, when he hiked to the top of a mountain and prayed with a group of people.
Bae said he had been moved by his faith to preach in the DPRK.
"I know Jesus wants me to become a path to (the DPRK)," Bae said in the remarks at the St Louis church in December 2011, of which an audio recording was posted on the church's website.
Church officials declined to comment on the contents of the website. The recording has since been removed.
Washington has appealed for Bae's release. In previous cases of US citizens being imprisoned in the DPRK, releases were secured by high profile visits, as the two countries do not have diplomatic relations.
Bae's case was handled by the Swedish embassy in Pyongyang, which has declined to comment on the case.
Two US journalists sentenced to 12 years in 2009 were released after a visit by former US president Bill Clinton.
Bae was first sent to China for a two-month mission trip by Hawaii-based evangelical group Youth With a Mission in 2006, according to his posts and the KCNA report.
Bae moved to the Chinese border city of Dandong in 2010 and carried out his own missionary work inside the DPRK, according to the St Louis church website.
"From this year, I am working at taking short-term mission teams into (the DPRK)," Bae said in the audio recording.
The DPRK has religions denominations including Protestant and Catholic churches, Christian groups say. The two Protestant churches in Pyongyang are open to visitors.
KCNA said Bae's crimes could have been punished by death, but the sentence was cut to 15 years hard labor after he admitted to the charges.
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