A South Korean human rights organization is pushing for the publication of a report on mass graves of the victims of North Korea's human rights violations next year, a U.S. broadcaster monitored here reported Tuesday.

The Seoul-based Transitional Justice Working Group (TJWG) plans to publish its first report on the collective graves in April or May, insisting it has gotten a grasp of 12 places believed to have such mass graves through interviews with 277 North Korean defectors and satellite images since last September, Radio Free Asia (RFA) said.

"We have to find out down the road where the victims (of the North's human rights violations) have been interred, how many they are and how they were killed," TJWG leader Lee Young-whan said, adding that the group is also gathering evidence on mass graves that can be used in future judicial procedures.

The group plans to expand the number of defectors to be interviewed to 500 per annum from next year, he said.

North Korea is known to have operated makeshift crematoria exclusively for those who have died or have been executed at correctional centers and is believed to have buried their remains en masse in certain places. (Yonhap)