North Korean children are “constantly in danger” of sexual abuse and resulting social stigma without any chance to seek legal protection, a Seoul-based rights group said on Wednesday.

Activists with PSCORE, or People for Successful Corean Reunification, interviewed more than 200 young male and female North Koreans who had fled to settle in the affluent, democratic South for a study on child abuse at home, at school and in state facilities such as prison camps and orphanages.

In a 195-page report, “Inescapable Violence: Child Abuse within North Korea”, the group described sexual abuse as “institutionalised and widely accepted as a normal part of life”.

“Children are constantly in danger of being sexually harassed, and have no legal recourse available to them,” the report said.

At school, for instance, teachers are “most often the perpetrators” who could physically harass female pupils and openly make lewd comments.

In one instance, a defector in her 20s testified her teacher said during class that one of the students must have “better stamina for sexual intercourse” because she had darker skin.

Another defector who said she became a trader at age 14 to make a living said she had struggled to keep men from groping her breasts and buttocks while travelling to markets by buses and trains.

One day she saw a stranger man rape a woman lying next to her at a dark inn room that dozens of people shared due to train failure, but her aunt sleeping nearby forced her to keep quiet to avoid “inviting trouble”.

Gathering information in North Korea is notoriously difficult, and Reuters was unable to independently verify the defectors’ accounts. North Korea has previously rejected criticism over human rights abuses as false accusations aimed at toppling its regime.

Last year, Human Rights Watch also reported “endemic” sexual abuse in North Korea based on interviews with some 100 defectors, although it acknowledged its survey was too limited to provide a generalised sample.

PSCORE said the rampant abuses constitute a breach of a U.N. convention on children’s rights, to which North Korea is a signatory. U.N. investigators have also criticised human rights violations in North Korea including the use of political prison camps where executions, rape and starvation take place.

“The lack of government response crystallises the notion that child sexual abuse is tolerated, and results in the rampant social stigmatisation that prevents victims from reporting their abuse,” PSCORE said.