The unification ministry on Sunday urged North Korea to immediately send a South Korean pastor and five other nationals back home, condemning their yearslong detention as "illegal and inhumane."

The ministry made the appeal in a statement marking 10 years after South Korean pastor Kim Jung-wook was arrested in Pyongyang in 2013 and then sentenced to hard labor for life on charges of spying for South Korea's spy agency.

In 2014, two other South Korean missionaries, Kim Kuk-gi and Choe Chun-gil, were also detained in the North on charges of committing what the North's regime called anti-North Korea crimes. Three former North Korean defectors, who had obtained South Korean citizenship, were detained in 2016.

"The government condemns North Korea's illegal and inhumane measure and strongly calls on North Korea, a signatory to the International Covenants on Human Rights, to immediately send them back to their beloved family members," Koo Byoung-sam, spokesperson at the ministry, said in the statement.

He said the government will work closely with the religious community and civic groups to find out the whereabouts of the detainees and win their repatriation, and cooperate with the international community to help resolve the issue.

"If North Korea has any understanding about human rights, it should not avoid the basic human rights issue any longer," Koo said.

President Yoon Suk Yeol has taken a hard-line stance against the North's provocative acts and has stressed the need to make the international community aware of North Korea's human rights abuses.

Last month, the ministry set up a task force to handle South Korean detainees, abductees and prisoners of war in North Korea. (Yonhap)