Japan's delegation in North Korea demanded Tuesday that officials there put the highest priority on finding out what happened to the 12 Japanese nationals who Tokyo believes were abducted and may still be alive.

The abductees are the "most important" issue in what North Korea bills as a comprehensive investigation into all Japanese individuals residing there, lead delegate Junichi Ihara told his North Korean hosts at the outset of two days of talks in Pyongyang.

The North Korean side is headed by So Tae Ha, chairman of the special investigation committee.