Father Philippe Blot, who works with the Paris Foreign Mission Society, described the situation facing North Korean refugees as "becoming ever more dramatic" as they flee to China to avoid dying of hunger.
"The 200,000 North Koreans now in China shouldn't be forcibly repatriated," he said in an interview with France's Le Monde daily March 30. "They all know they'll be tortured, sent to camps and killed if this happens."
The priest said he had been asked for help from refugees while ministering in South Korea's Andong and Suwon dioceses, and had gone to China in 2010 to help establish a reception network.
Each refugee was charged up to $5,300 by traffickers, and their key concern was for family members still in the country, he said.
"When a North Korean flees, his family (is) considered traitors and sent to re-education camps. So we first have to verify whether they've been seized before trying to help via our North Korean contacts," Father Blot said.
"But those in China are still in an illegal, dangerous situation. As a priest, I face a moral problem, since I'm also placing myself outside the law and Christians should obey the law. But moral criteria are surpassed since China is trampling on human rights. So instead, I follow Gospel criteria," he said.
North Korea remains home to the Catholic dioceses of Hamhung and Pyongyang, although active clergy were killed or deported during and after the 1950-1953 Korean War.
Services are permitted at one officially approved Catholic church in Pyongyang, the capital, a city of 2.7 million, as well as at two Protestant churches and an Orthodox church. In 2008, a South Korean Franciscan, Father Paul Kim Kwon-soon, became the first priest given a residency permit.
The country was home to about 100,000 Catholics and up to 200,000 Protestants before the communist takeover. Human rights organizations estimate that at least 30,000 Christians are incarcerated in prisons and labor camps.
Father Blot said Christians had been publicly executed for illegally keeping Bibles and rosaries. Churches that remain open are "just facades" for a "sham religious liberty," he said.