A South Korean NGO has discovered hundreds of locations across North Korea that are used for public executions under President Kim Jong Un.

The Transitional Justice Working Group said Tuesday that they had identified 318 public execution sites in total, based off interviews with 610 North Korean defectors over four years. The summaries of the findings were published in a report called "Mapping The Fate Of The Dead: Killings And Burials in North Korea"

The individuals condemned to the public executions were alleged of crimes such as "murder or attempted murder, stealing copper, human trafficking, stealing cows and other forms of property and economic crimes," the report said.

The executions are often carried out by firing squad, and a crowd of up to 1000 people could be present to witness the event.

"Brief 'trials' almost always occur on the spot immediately before a public execution, where charges are stated and a sentence given without legal counsel for the accused," the report said. "Interviewees reported a recent incident when the guards used hand-held metal detectors to find and confiscate mobile phones from witnesses at a public execution to prevent them from recording the events. This suggests regime concern about information on public executions getting out of the country."

The human rights watchdog Freedom House says that in regards to human rights, Kim Jong Un's North Korea is "not free." The organization adds that "Surveillance is pervasive, arbitrary arrests and detention are common and punishments for political offenses are severe." There are also allegedly 80,000 to 120,000 political prisoners in the country.

The President of North Korea, Kim Jong Un, assumed office as Supreme Leader after the death of his father Kim Jong-Il, who had governed the country for 17 years.