LONDON, UK — Last month, filmmaker John Sweeney traveled with a group of students from the prestigious London School of Economics (LSE) on a government-sanctioned tour of North Korea.

Sweeney’s resulting 30-minute documentary on the secretive, oppressive state aired Monday night on the BBC’s Panorama program. LSE staff and students, however, say that Sweeney and his colleagues misled the students about their intentions. They claim the filmmakers used them as “human shields” for otherwise prohibited journalism without their knowledge or consent — a claim the filmmakers protest — and that the BBC’s actions endangered the students, the school and the future of such visits for all institutions.

Speaking to the Guardian newspaper from New York, LSE director Craig Calhoun said that some of the 10 students who went on the trip have received threatening letters since the filmmakers’ presence was uncovered, and that the North Korean government has complained.

“The subterfuge was employed, ironically, because the North Korean government considers BBC and other independent journalists akin to British spies,” Calhoun wrote in the Times Higher Education Supplement. “The danger now is that the North Koreans, and governments in equally sensitive parts of the world, will think the same of LSE staff and students. The entire enterprise was reckless and irresponsible from start to finish, as well as deeply dishonest.”

The only party deceived in the affair, the BBC counters, was the North Korean government.

The students “were told about the risks in London, twice,” Sweeney wrote on his Twitter feed.

Students were informed on three separate occasions that there would be journalists traveling with them and that as a result they could risk deportation, arrest, and possibly detention, said Ceri Thomas, the BBC’s head of news. North Korea grants visas to foreign academics, but not to foreign journalists.

LSE was never mentioned in the half-hour show that aired Monday. In a voiceover, Sweeney said that he entered North Korea “undercover” as part of a tour group accompanied at all times by government minders. Images of some of the students on the tour were pixelated over.

The camera captured intriguing images in what Sweeney called “the strangest nation on Earth.” Minders took the group to a bottling factory with still and silent machines and to a hospital with no patients. (“They were here and they left,” a white-coated doctor explained.)

“No photos, no photos!” the guides can be heard shouting when the camera captures the rare glimpse of North Korea’s poverty through the bus windows — a woman washing her clothes in an icy river, two men scavenging in the mud.

The trip took place March 23-30, a month after North Korea tested a nuclear weapon and launched a new wave of bellicose threats at South Korea and the United States.

According to multiple reports, it was organized by Tomiko Newson, an LSE alum who is married to John Sweeney. Newson contacted the Grimshaw Club, an international relations-focused student society at LSE, to invite interested students on a trip she was organizing, the Guardian newspaper reported.

Ultimately, 10 students ages 18 to 28 paid to come on the trip. The BBC has reported in its own coverage of the affair that students were told twice prior to leaving that there would be one undercover journalist traveling with them. When they got to Beijing, their last stop before Pyongyang, they learned there would actually be three journalists: Sweeney, Newson and BBC cameraman Alexander Niakaris.

The students were not given more information in order to protect them in case the ruse was discovered, the Guardian reported, citing a “senior BBC source.”

“BBC staff have argued that this lack of frankness in denying the genuine members of the group the full details was done for their own benefit in the event of discovery and interrogation by North Korean authorities,” the LSE wrote in an email sent on Saturday to staff and students.

“It is LSE's view that the students were not given enough information to enable informed consent, yet were given enough to put them in serious danger if the subterfuge had been uncovered prior to their departure from North Korea.”

The Panorama controversy is just the latest in a string of ethical scandals to rock the BBC. In September, news broke that the broadcaster had failed to investigate numerous child sexual abuse charges against the late former presenter Jimmy Savile. Director General George Entwistle resigned in November after just 54 days on the job after a member of the House of Lords was falsely accused of child molestation on air.

“Investigative journalists must sometimes employ subterfuge. That is not our objection,” Calhoun wrote in the Times. “Our objection is to the BBC using our name and our students to support that subterfuge, without properly informing either the school or the students of their plans so that they could judge the risks."