North Korean leader Kim Jong Un has increased interrogation and torture of citizens caught escaping to China, an international human rights group said Tuesday. Human Rights Watch, a non-governmental advocacy organization based in New York City, said in a statement Tuesday a U.N. investigation will shed light on developments in North Korea when it presents its findings to the U.N. Human Rights Council in March. The comments came as the group's 667-page "World Report 2014," and annual review of human rights practices in 90 countries, was released Tuesday. "Kim Jong Un has picked up where his father and grandfather left off, by overseeing a system of public executions, extensive political prison camps and brutal forced labor," said Phil Robertson, deputy Asia director of the organization. Despite having ratified several U.N. human rights treaties, North Korea continues to repress civil and political rights and continues to practice collective punishment known as kwan-li-so, in which three generations of an offender's family join the offender in forced labor camps, the statement said. It added former North Korean security guards told Human Rights Watch those caught after escaping to China are systematically interrogated and tortured.