Yonhap via Reuters

Kenneth Bae, 44, was convicted of "hostile acts" against North Korea.

An American tour operator sentenced to 15 years of hard labor in North Korea has begun his sentence at a “special prison,” state media reported Wednesday.

Kenneth Bae, 44, stood trial last month accused of “hostile acts” against the repressive regime.

Bae, who is from Washington state, was convicted of an attempt to topple the government through “state subversion” according to a brief report on the Korean Central News Agency's website.

“Pae Jun Ho, an American citizen, started his life at a special prison on Tuesday,” the report said, referring to him by his Korean name.

He is one of at least three other U.S. citizens who are also devout Christians to have been detained by North Korea in recent years.

While North Korea's constitution guarantees freedom of religion, in practice only sanctioned services are tolerated.

Washington state Rep. Cindy Ryu told The Herald newspaper in December that Bae might have been doing missionary work in North Korea.

"Many of us are third- and fourth-generation Christians and many of our pastors are originally from North Korea," Ryu said. "We want to visit our home country, but in North Korea you cannot say you are a missionary."

A Facebook page has been set up titled “Remember Ken Bae, Detained in North Korea.”

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SEOUL -- An American tourist who visited North Korea last month for what was to have been a five-day trip has been detained by police there, associates of his family and activists in Seoul said.

Kenneth Bae, 44, was in a group of five tourists who visited the northeast city of Rajin, South Korea's Yonhap news agency said, citing a report by the Kookmin Ilbo newspaper. Bae, who is Korean-American, entered North Korea on Nov. 3.

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"What we know is that he is a person who wants to help poor children, kotjebis (homeless children), and he took pictures of them to support them later," said Do Hee-youn, a North Korean human rights activist and head of the Citizens' Coalition for Human Rights of Abductees and North Korean Refugees.

'Fluttering swallows'
There are said to be thousands of homeless, starving children in the North after a famine in the 1990s. Kotjebis translates into English as "fluttering swallows."

It was impossible for NBC News to confirm Bae's arrest in one of the world's most secretive states and there has been no formal announcement on North Korean media.

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The Swedish Embassy in Seoul did not immediately respond to an inquiry about whether it was aware of the arrest. Similarly, the press officer at the Swedish Embassy in Beijing declined comment when contacted by NBC News.

Sweden handles the affairs of U.S. citizens in North Korea because Washington does not have diplomatic relations with Pyongyang.

Kookmin Ilbo, owned by an evangelical church in Seoul, reported it was expected Bae could be released in two or three weeks. The paper cited an unidentified source and it was not possible to confirm the report.

It cited sources as saying Bae had been arrested for carrying a computer hard disk which contained footage of North Korea executing defectors and dissidents. This was also impossible to verify.

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History of trouble
U.S. citizens of Korean descent have previously run into trouble in the North. Robert Park, a missionary, was detained after entering the country in late 2009 and says he was tortured for protesting against the country's human rights record.

Earlier that year, former President Bill Clinton flew to Pyongyang to secure the release of two American journalists who had entered North Korea illegally.

The U.S. State Department declined to comment on the reports.

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"I don't have anything for you on that one way or the other, for privacy reasons," State Department spokeswoman Victoria Nuland told a news briefing.

A pastor at a Korean church in Washington state, who said Bae's mother attended services there, said the mother, Myung Bae, had prayed for her son's release Wednesday morning after learning of his detention from news reports.

"She just learned that he had been detained," pastor Chan Song of the Korean Emmanuel Church in the Seattle suburb of Lynnwood told Reuters. "She's scared. ... She doesn't know how he was detained."

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Bae's mother has attended a morning prayer group at the church for several years, the pastor said, but her son was not a member of the church. Efforts to contact the mother at her Washington state home were unsuccessful.

The office of state Senator Paull Shin, a Korean-American whose district includes parts of Lynnwood, was trying to find out more but was not in contact with the family, legislative assistant Jeff King told Reuters.

On Wednesday, North Korea sparked calls for sanctions from Washington and others when it fired a long-range rocket that put a satellite into space.

Critics say the North is breaching U.N. Security Council resolutions that prohibit it from activities linked to nuclear development or missile technology.

NBC News' Ed Flanagan in Beijing and Reuters contributed to this report.

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