A diplomatic row is brewing between Seoul and Beijing over the claims by Kim Young-hwan, a South Korean activist for North Korean human rights, that he was severely tortured by Chinese security officials during his 114-day detention in the neighboring country.

China’s Foreign Ministry flatly denied the claims on Tuesday, saying that the Chinese authorities that handled the case conducted an investigation “according to the law” and protected the legitimate rights of Kim and three other arrested South Koreans.

The ministry added that China had already conveyed its position to the South Korean government.

The ministry’s denial is disappointing and inconsiderate, as it would put Beijing in hot water and unnecessarily cause friction between the two nations.

Yet it is not a totally unexpected response, given that admitting the claims amounts to openly acknowledging that China is a country where foreign citizens are still tortured. Beijing obviously wants to avoid such a stigma.

But it would be a grave mistake for it to think that the row would subside without an apology to the torture victim. If it continues to reject the victim’s claims, it will have to face global condemnation for its gross disregard for human rights.

Kim at first refrained from offering a detailed account of the torture he suffered during his detention. He did not want to highlight human rights issues in China because it would eclipse an issue far more important to him ― human rights abuses in North Korea.

Yet he changed his mind and vividly recounted his ordeal to the media on Monday before testifying to the National Human Rights Commission of Korea. He explained that he wanted to bring pressure on Beijing to stop harassing South Korean rights activists working for North Korean defectors in China.

According to Kim, he underwent intense abusive acts in the first month of detention. He was deprived of sleep from April 10 to 15 and underwent severe beatings and electrical torture from the night of April 15 until dawn on the following day.

Before torturing Kim, Chinese security agents checked his blood pressure and collected a blood sample, suggesting the torture was instructed by a high-ranking official.

Kim said masked agents tortured him with a cattle prod wrapped with electrical coils for five to eight hours. “I could smell my flesh burning as I was tortured,” he was quoted as saying.

The agents also beat the victim badly on the face until “my face turned red with blood.”

Kim also suffered other physical abuses, including laboring for 13 hours a day eating nothing but a small loaf of bread and being forced to wear handcuffs and stand for long hours, which paralyzed his hands.

As China denies his torture claims, Kim and his supporters are planning to bring the case to international organizations, including the International Criminal Court, the U.N. special rapporteur on torture and the U.N. Office of the High Commissioner for Human Rights in Geneva.

They also plan to file a complaint with the Committee against Torture, which monitors the implementation of the U.N. Convention Against Torture by state parties. China signed up to the convention in 1988.

But even as he sought investigation into his case by international agencies, Kim said he did not want to see a conflict emerge between Seoul and Beijing or to put China in trouble.

He said all he wanted was an apology from Beijing and a promise that similar incidents would not take place in the future.

Kim’s demands are modest. Yet he won’t get China to apologize easily. For one thing, there is no physical evidence of torture that would compel China to admit the wrongdoing by its security agents. Kim’s wounds caused by torture all healed without leaving any marks.

As Kim’s only option is to drum up international pressure on China, the Seoul government needs to help him take his case to the U.N. and other multilateral agencies.

The government also needs to step up efforts to have China launch an investigation to verify Kim’s claims. Beijing has not yet officially responded to the government’s demand that it conduct a thorough probe into the case.

Beijing should pluck up the courage to admit the torture claims and offer an apology. It needs to use the case as an occasion to check its treatment of other arrested South Koreans. Otherwise, it cannot avoid becoming the butt of global criticism.