Tokyo: A North Korean scientist involved in the regime's biological and chemical weapons programs has defected, apparently with evidence of tests on human subjects.

The researcher, who has only been identified by his surname, Lee, was based at a microbiology research centre in Ganggye, near the Chinese border, but defected on June 6, South Korea's Yonhap news agency reported.

North Korean soldiers stand guard outside their post along the river bank of the North Korean town of Sinuiju, opposite the Chinese border city of Dandong in March. Credit:AP

Mr Lee, 47, fled to Finland via the Philippines, according to a group that campaigns for human rights in North Korea.

He was carrying an electronic data storage device allegedly containing 15 gigabytes of information on Kim Jong-un's regime's use of humans to test biological and chemical weapons.