SEOUL, South Korea — Set on 250 sprawling acres in North Korea’s capital, the Pyongyang University of Science and Technology obeys the rules of the Kim family cult.
Atop its main building, large red characters praise “General Kim Jong-un,” the country’s provocative young leader. At the front of lecture halls hang smiling portraits of his father and grandfather, who led the nation before him.
Yet the school is different in one striking way. In a country that bans religion, it is run by evangelical Christians.
Founded seven years ago by a South Korea-born American, the school has thrived because of a deal with the leadership. It provides children of the North Korean elite with an education they cannot get elsewhere — computer science, agriculture, international finance and management, all conducted in English by an international faculty. Its teachers, half of them American, are forbidden to preach.
While the university’s chancellor, Park Chan-mo, said the arrests were not related to the teachers’ work at the school, the men were accused of “hostile acts,” a charge that is often used against people accused of spying or proselytizing.
That effectively makes them bargaining chips in the high-stakes conflict between Pyongyang and Washington. As Mr. Kim pursues a destabilizing nuclear weapons program and the Trump administration warns that the time for “strategic patience” is over, the school gives the regime access to a rare commodity in their country: American citizens.
The volunteers’ arrests have also cast a light on the school and the ways in which critics say it has, perhaps inadvertently, aided the regime.
Some of those critics say the school is training the future elite of a dictatorial regime that abuses human rights and threatens its neighbors with nuclear weapons. Right-wing activists in South Korea accuse the school of educating future hackers.
The school “cannot operate in North Korea without making compromises to the regime — either in money or information — and I am uncomfortable with the extent of such a compromise,” said Suki Kim, who taught English at the university in 2011 as a journalist working undercover. She later described her experience in the book “Without You, There Is No Us.”
Many of those compromises are apparent on campus.
Students march to the cafeteria singing songs swearing loyalty to Mr. Kim. Course materials have to be approved by the North Korean authorities, who have their own staff members installed on campus. Faculty members must have “guides” with them when they venture off campus.
While the foreign faculty has unfiltered access to the internet, most students do not. Teachers have to watch what they say — students are required to report any subversive comments.
One American professor was deported for trying to give a student a Bible.
An obelisk at the university, erected by the North Korean authorities and dedicated to Mr. Kim’s grandfather and father, has drawn scorn from outside observers.
“Korean churches have ended up building a temple of idol worship there,” said the Rev. Lee Ho, the leader of the anti-Communist Holy Korea Network.
The university said the monument and other state propaganda were “obligatory,” and “normal” elements of all schools and other official establishments in North Korea.
For the staff of about 90 foreign volunteers from a dozen or so countries, teaching at the university is a chance to gain a foothold in an atheistic country by befriending future North Korean leaders and teaching them an international mind-set.
The volunteers mingle and eat with the 500 or so handpicked students, who live on the campus. Together with their families, the staff constitutes the single largest foreign community in North Korea.
The teachers, many of whom are Korean-American missionaries, are allowed to practice their faith among themselves. But the one inviolable rule is that they are not allowed to proselytize.
“We want to teach the North Koreans how to catch fish, rather than giving them fish,” said Mr. Park, also a Korean-American and a former president of South Korea’s prestigious Pohang University of Science and Technology. “This will help narrow the economic gap between the two Koreas and the cost of the eventual reunification.”
Thae Yong-ho, a North Korean diplomat who defected to the South last year, said the university was popular among the children of the elite and taught them market principles in a country desperate to modernize its economy. Mr. Thae also dismissed the allegation that the school was training future hackers.
And indeed the university continues to grow, with plans to add a new medical school to the campus in southern Pyongyang.
Despite being in the spotlight, the school is trying to play down the significance of the volunteers’ arrests.
One of the detainees, Kim Sang-duk, an accounting teacher who is also known as Tony Kim, had frequently visited the northeast, where he distributed humanitarian aid to children’s homes and recently delivered 20,000 blankets to flood victims, school officials said.
The other, Kim Hak-song, a Christian pastor, supervised an experimental farm on campus, visiting for a month at a time from China, where he worked as a missionary for a Los Angeles church, according to school officials and the church’s website.
Both were detained as they were trying to leave the country. The government has provided no further details on their cases, including whether they are linked.
“We were told that their detentions had nothing to do with what they did at the school and that otherwise they would have been arrested on the school ground,” Mr. Park said during an interview in Seoul, the South Korean capital. “We are praying for them.”
The school has reminded its faculty of local rules, but otherwise life there continues in a “perfectly normal manner,” the school said in a statement for this article. Several volunteers from the school have left North Korea in recent days, as planned and without incident, it said.
The university also says it takes care not to violate United Nations sanctions.
“We are in regular dialogue with officials in the U.S. and other administrations on this point, including sharing details of our curriculum,” the statement said.
When the university’s founder, Kim Chin-kyung, who is also known as James Kim, visits South Korean churches to raise money, he asks congregants to “pay a price” for reunification and for their fellow Koreans suffering in the North, an appeal that resonates with many Christians in the South.
He argues that reconciliation is the only way to achieve reunification of the divided Korea, and that Christian love can help nurture it.
“I am not a capitalist, I am not a Communist, I am a love-ist,” he likes to say.
Whether or not that works, the school has surely opened the minds of some students a bit simply by allowing them contact with foreigners.
Will Scott, an American computer scientist who taught there from 2013 to 2015, said some of his students admitted to “having nightmares” when they first met teachers from the United States, a country they had learned to demonize from childhood.
But the students were eventually able to channel their hatred toward the American government and came to accept the individuals they met there.
“Many of the students were at the university more for the chance to get to interact with foreigners than for the specific major they were in,” Mr. Scott wrote in a question-and-answer session on Reddit.
But the government tries to reinforce loyalty, requiring the students to take a class on the state ideology of juche, or self-reliance, every Saturday.
When Chancellor Park complained that the class would not give students enough time to do their homework, he said a North Korean administrator had a pointed retort.
“Mr. Chancellor,” he said, “you yourself go to church every week, don’t you?”