Thai law professor Vitit Muntarbhorn, in a report to the UN General Assembly, said that its government is using public executions as a means of intimidating the population, and using spies to infiltrate and expose religious communities, The Times reported.
His report came two days after the World Food Programme said that two thirds of North Koreans do not have enough to eat, in the country's worst crisis since as many as three million people died of famine a decade ago.
"Sadly, even though the harvest was getting better, we have had devastating floods in 2006 and 2007. Over the past year we have had very worrying information of a very chronic food shortage," Muntarbhorn said in New York.
He acknowledged that the government of Kim Jong Il, North Korea's supreme leader, has allowed access by international agencies to areas damaged by floods in 2007, but described the overall human rights situation as grave.
"Particularly disconcerting is the use of public executions to intimidate the public. This is despite various law reforms in 2004 and 2005, which claim to have improved the criminal law framework and related sanctions," he said.
Available food is disproportionately directed to the political elite, the media is controlled by the state, there is no political participation, and dissidents and those with religious faith are persecuted, as well as those who return to North Korea after illicitly leaving the country across the Chinese border.
Muntarbhorn decried severe constraints on civil and political rights in North Korea, citing reports of "a clampdown on cellphone and long-distance telephone calls to prevent people from reporting on food shortages."
Recent visitors to the country report that North Koreans are no longer allowed to use mobile phones at all. The few foreign tourists who travel there are made to surrender their mobiles on arrival; these are then sealed and returned only when departing the country.
Government officials blame cases of spying for the crackdown. There are however reports that a Korean mobile phone service, which would not be able to communicate with the outside world, is being planned for a possible launch early next year.
On Tuesday, WFP announced that some 2.7 million people on North Korea's west coast will run out of food in October, and that, because of the worsening food situation, it was increasing from 1.9 million to 6.5 million the population which it seeks to help with food aid.