According to reports in state run media, the highest court in the secretive nation passed down the judgment as a lesson to those tempted to conspire with Washington and Seoul.

Two South Koreans accused of spying were sentenced to a lifetime of hard labor at a time when North Korea’s humans rights record is coming under increased scrutiny, according to Reuters.

North Korea Sentences "Spies" To Hard Labor For Life

Sentencing announced by North Korean state media

Reports of the sentencing surfaced at the same time as the opening of a United Nations field office in the South Korean capital of Seoul, from which the organization will investigate alleged human rights abuses carried out by the Kim regime in North Korea.

Officials in Pyongyang are angry at the plans to investigate practices in the secretive country, and the government denies any wrongdoing. However defectors have claimed that dissidents are thrown into prison camps, and reports recently surfaced of a series of grisly executions involving anti-aircraft guns, which were allegedly part of a political purge carried out by leader Kim Jong-un.

The latest sentencing involves two men, Kim Kuk Gi and Choe Gun Gil. North Korea accuses the two men of carrying out espionage activities from their base in the Chinese border city of Dandong. The two men were arrested in March, with officials claiming that they were working for South Korea’s National Intelligence Service (NIS).

Prosecution pushed for death penalty

According to North Korea’s KCNA news agency, the pair were convicted of a number of charges including conspiracy to overturn the state, espionage, illegal entry and working under the control of the U.S. and South Korean governments.

The agency reports that the prosecution had pressed for the death penalty, but the defense counsel for the two men requested leniency.

“The crimes of the spies of the puppet intelligence agency prove that the United States and the puppet South are the masterminds of political terror and kingpins of trickery and show what miserable plight awaits those who conspire with them,” it said.

Official dispatches from North Korea are famed for their flowery language and elaborate insults, which contributes to the almost comic image that some Westerners have of the Kim regime. However it should not be forgotten that behind the overwrought accusations there lies a regime which has no qualms about sending human beings to labor camps.

For its part the NIS claims that the allegations are “groundless.” However both men claimed to have spied for the South during interviews with CNN in May. South Korea’s relations with the North are the responsibility of the Unification Ministry, which responded to news of the sentences by expressing its “strong regret” and demanding that the pair be liberated.

UN to investigate alleged human rights abuses

Despite Pyongyang’s attempts to heavily restrict the flow of information in and out of the country, reports of human rights abuses are widespread.

“Less than 50 miles (80 km) from here lies another world marked by utmost repression and deprivation,” said Zeid Ra’ad Al-Hussein, the U.N. High Commissioner for Human Rights, during the inauguration of the U.N. office in Seoul.

U.N. staff will set about investigating human rights abuses north of the border, which a U.N. Commission of Inquiry report claimed were as important as atrocities carried out by the Nazis.

North Korea is currently also holding a South Korean citizen who possesses a U.S. green card, as well as a South Korean missionary. In 2014 officials released three Americans, one of whom ad been detained for two years after working as a missionary.