A notice indicating the closure of the shop is placed behind the window of the coffee shop owned by Canadian couple Kevin Garratt and Julia Dawn Garratt in Dandong, Liaoning province, August 5, 2014. REUTERS/Ben Blanchard

By James Pearson and Ben Blanchard

SEOUL/DANDONG China (Reuters) - A Canadian man under investigation in China for threatening national security said he ran a prayer and training facility outside the Chinese city of Dandong which was frequented by North Koreans, many of whom were converted to Christianity before re-entering the isolated country.

Kevin Garratt, who with his wife Julia Dawn Garratt is being investigated for suspected theft of military and intelligence information, also ran a coffee shop in Dandong, which was closed on Tuesday with a notice in the window reading: "See you soon."

"When God says to go and do something - yeah we have a choice - but when God's presence says go, we really better go," Garratt said in an audio file posted on the website of Terra Nova Church based in British Columbia, Canada.

"All these people could've stayed in China, where it's easier, where they could eat three meals a day," he added, addressing a congregation at the South Korean-Canadian church in Canada last November.

"But they chose to go back - everyone of them. And 99 percent of the people we meet go back to North Korea, because they have to preach the gospel in North Korea - they have to. Because God's compelled them to go."

Terra Nova Church and its pastor did not reply to several emails and calls for comment on the audio file, although some were sent and made outside regular office hours.

Garratt's claims, which could not be independently verified by Reuters, were likely to cause consternation in North Korea, a secretive country where religion is banned and proselytising is severely punished.

Peter's Coffee House, run by the Garratts on the border with North Korea, advertises tours to North Korea on its website.

Kevin Garratt leads the tours and knows North Korean tour guides, some of whom frequent the shop on rare visits to China, said a source familiar with the trips. The source declined to be identified due to North Korea's sensitivity to religious groups.

The case bears similarities to that of U.S. missionary Kenneth Bae, who was sentenced by Pyongyang last year to 15 years hard labour for attempting to overthrow the state.

Bae operated businesses in Dandong and he used his tour company Nation Tours to take foreign missionaries across the border into North Korea.

WHEREABOUTS UNKNOWN

China's Foreign Ministry said on Tuesday that the Garratts were under investigation. Their whereabouts are unknown. None of the couple's three adult children could be reached by Reuters for comment. One of their sons, 27-year-old Simeon Garratt who lives in British Columbia, told Hong Kong's South China Morning Post that his parents were "openly Christian" and that they sent goods such as food supplies to impoverished North Korea.

Neither the Chinese Foreign Ministry nor the official Xinhua news agency, which first announced the probe, mentioned religious activities.

But doing anything that could be seen as overtly religious along the sensitive border with North Korea was risky, experts said. "North Korean authorities cooperate really closely with China basically throughout the border region ... of course there is more risk along the border," said Adam Cathcart, a specialist on China-North Korea ties at the University of Leeds.

The Garratts did little to hide their Christianity, according to people who had been to their Dandong cafe, which they said was known as a meeting point for foreign Christians in the area.

"It couldn't be any more Christian, it's always busy and they play Christian rock music in there," said Gareth Johnson of Young Pioneer Tours, a travel company based in China that takes tourists to North Korea and who has visited the shop.

The cafe was closed on Tuesday when a Reuters reporter went there. A notice on a chalkboard in the window said "see you soon". Nearby, a laminated sign posted on the cafe's wall said "Let your faith be bigger than your fear".

While China can be suspicious of Christian groups, underground churches and foreign missionaries usually operate without too much harassment, experts said.

"North Korea, as you know, is very oppressive, it's very challenging, they desperately need hope, and we get this very special privilege of working with some of these incredible people in North Korea," Garratt said in his address last year.

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