THE gruesome sketches need little explanation. They are based on the memories of Kim Gwang-il, a North Korean who spent more than two years in a prison camp before eventually escaping through China and Thailand to South Korea. The pictures show prisoners held in stress positions, skeletal bodies eating snakes and mice, and prisoners pulling a cart laden with rotting bodies. But none of the pictures, he says, was nearly as graphic as the reality of being forced to live in the camp.

Mr Kim was one of over 80 defectors, refugees and abductees who publicly testified before a commission of inquiry (COI) set up by the UN’s Human Rights Council in March 2013 to investigate systematic human-rights violations in North Korea. It interviewed another 240 victims confidentially (many fear reprisals on family members still in North Korea). After a year-long investigation, on February 17th the commission delivered its 400-page report.

The report, written by a three-member UN panel headed by Michael Kirby, an Australian former judge, is extraordinary in its detail and breadth. It includes a catalogue of cruelties meted out by the North Korean regime to its main targets: those who try to flee the country; Christians and those promoting other “subversive” beliefs; and political prisoners, estimated to number between 80,000 and 120,000. The regime is accused of crimes that include execution, enslavement, starvation, rape and forced abortion.

The report is also remarkable for the fierceness of its condemnation. It describes a totalitarian state that is without parallel in the contemporary world. Mr Kirby told journalists it was comparable to Nazi Germany. It urges the UN to refer the situation to the International Criminal Court (ICC) in The Hague. In a letter sent directly to Kim Jong Un, the North’s dictator, the commission warned that he could be held accountable for crimes against humanity.

North Korea has flatly rejected the UN’s accusations, just as it continues to deny the existence of its network of prison camps. It did not allow the commission to enter the country. Yet the hope is that the report marks a turning-point in the outside world’s approach to North Korea.

The COI says the international community “must accept its responsibility to protect the people” of North Korea. Although sceptics argue that the report amounts to little more than a call for more engagement (including inter-Korean dialogue and humanitarian aid), it may help to push human rights higher up the agenda. The commission says it does not support sanctions imposed by the UN Security Council (in a bid to curb North Korea’s nuclear-weapons development), due to the dire social and economic state of the population. If the six-party talks on denuclearising the Korean peninsula are ever resumed, it would be harder for them to take place without some discussion of the regime’s brutality. The American government will now no longer be able to prioritise one issue over the other, says Victor Cha of Georgetown University.

Equally striking is the indictment directed by the COI at China. Chinese leaders refused to let the commission visit its border provinces with North Korea and have opposed the commission’s inquiry from the start. They too received a critical letter from the commission, suggesting that they are “aiding and abetting crimes against humanity”. Refugees are routinely rounded up inside China and returned to North Korea, often to face imprisonment, torture and even execution.

China has a visceral dislike of human-rights investigations. It fears that condoning the exposure of other countries’ abuses might invite scrutiny of its own. It was therefore quick to dismiss the report as “unreasonable criticism”. Yet the language of the report, as much as the terrible detail within it, is likely to unsettle Chinese leaders, whose support in the form of oil and food shipments is considered by many observers to be vital to the survival of Mr Kim’s government.

Many assume that China would use its right of veto, as a permanent member of the UN Security Council, to block referral to the ICC. Adam Cathcart of the University of Leeds says that the impact of the commission’s report “hangs on China”. Yet China rarely vetoes a resolution alone. It would want to win Russia’s backing if the case reached the security council. And there are a few glimmers of hope: in 2012 China allowed to pass without a vote (rather than vetoing) a UN resolution condemning human-rights violations in North Korea. It is well aware that the price of supporting a regime that has committed crimes against humanity is high, especially for a country that wants to be a global actor. And though China says it has little leverage on North Korea, the report hands it more by raising the threat of the ICC.

Even if China itself does not come out well in the report, Chinese leaders may still feel a sense of Schadenfreude that North Korea is being described in this way. They have been intensely irritated by the behaviour of their ally in recent years, particularly by its testing of nuclear devices, most recently in February 2013. Mr Kim annoyed them further by hastily executing his uncle, Jang Sung Taek, in December. Jang had been an important interlocutor with China. Xinhua, the Chinese government’s news agency, posted a slide show on its website in December 2012 titled “The world’s 11 most brutal prisons”. North Korea’s Hoeryong prison camp featured as number one. Chinese censors have allowed some of the UN report’s findings to be discussed on social media.

But China has two big worries. One is that the Chinese public might step up criticism of their government’s support for the North. There have been signs of this on Chinese microblogs. Hu Xijin, who edits Global Times, a normally pro-party newspaper, wrote to his nearly 4.4m followers on Sina Weibo, a Twitter-like service, that the international community should “put pressure” on North Korea to pay greater respect to human rights. China’s leaders, however, still believe that confronting North Korea on such issues might prompt Mr Kim to become more bellicose. Avoiding war and the collapse of North Korea are China’s priorities.

Its other concern is that it might face more international pressure to halt the repatriation of North Korean refugees. This, it fears, could trigger an exodus that would overwhelm China’s border areas, attract involvement by meddling foreigners and an angry backlash by North Korea that could destabilise the peninsula. For China, North Korea is a headache. For its unlucky inhabitants, the country is something far, far more sinister.