The London School of Economics, one of Britain’s leading universities, has criticized the BBC for putting students at risk by allegedly using them as cover for a covert documentary film in North Korea.

The ten students were told “a journalist” would accompany them on their academic trip to North Korea in March, without informing the students of BBC’s intentions to use the visit to film a high-profile documentary on the secretive state until later, the university said. Three BBC journalists had joined the trip, including respected reporter John Sweeney.

Alex Peters-Day, general secretary of the LSE’s student union, said the students were only told of BBC’s plans at a very late stage, with one saying she was only informed when they were on the plane to North Korea, according to Reuters.

“Students were lied to, they weren’t able to give their consent,” Peters-Day said, adding that the students were used as “human shields”.

The BBC refused demands from the LSE to pull the documentary from the “Panorama” current affairs program due to air on Monday night.

Head of news programmes Ceri Thomas said the students had been properly warned ahead of the trip.

“We told them there would be a journalist on the trip, and if that journalist was discovered, it could mean detention and that it could mean arrest,” he said. “We have a duty to give enough information to people on a trip like this so they can give us fully informed consent.”