https://www.mnnonline.org/news/voice-of-the-martyrs-korea-to-add-fifth-daily-broadcast-to-north-korea/
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According to Pastor Foley, between 14 and 20 percent of North Koreans listen to foreign broadcasts through headphone radios purchased on the gray and black markets. He explains that because listening to such broadcasts can be done overnight in the dark in silence, it remains the primary way that North Koreans are able to access Christian content..."
