"His ostensible reason for defection is that he felt skeptical about his research," the South Korean Yonhap News Agency reported on Thursday, quoting a source from a North Korean human rights group.
The 47-year-old researcher from a microbiology research center in Ganggye, Chagang Province in North Korea, identified only by his surname Lee, reportedly fled to the European country on June 6 via the Philippines, according the source.
The motive for Lee's defection was his intention to reveal the inhumane tests North Korea carries out on human subjects by testifying before the European parliament later this month, the agency reported.
Finnish local media reported that Finland's Ministry for Foreign Affairs, Ministry of the Interior and the Finnish Immigration Service could not confirm nor deny the information.
Earlier in December, several defectors from North Korea claimed that the country conducts experiments on disabled people, including children, in order to test chemical and biological weapons. Similar claims were revealed in a study by the Citizens' Alliance on North Korean Human Rights, published in 2013.
A United Nations Commission of Inquiry on Human Rights in the Democratic People’s Republic of Korea said it was familiar with the allegations of medical experiments performed in "closed hospitals" on "persons with disabilities" in 2014. However, previously, it was not possible to corroborate the claims due to a lack of evidence.