South Korean government said Wednesday that it will track some 4,000 unregistered babies born to mothers of foreign nationality between 2015 and 2022, although it said it technically has no legal obligation to do so.

“In order to expand the protection scope for ‘ghost babies,’ the government will begin its investigation to confirm the whereabouts of babies born to foreign mothers, too,” said First Vice Health Minister Lee Ki-il.

Last month, the state audit agency said it had discovered a total of approximately 6,000 babies born in local hospitals but not included in the country‘s birth registration system. Nearly two-thirds of them were born to parents registered as foreign nationals here, according to officials.

Under the Family Relations Registration Act until it was revised last June 30, infants born to parents of Korean nationality were required to be registered by the parents within a month of their birth, but infants born to parents of foreign nationality were not required to be registered here at all. Following the revision, infants born to parents of Korean nationality are now required to be registered by medical institutions within 14 days of their birth, whereas infants born to parents of foreign nationality are still not required to be registered at all.

On Friday, the Ministry of Health and Welfare wrapped up preliminary investigations of about 2,000 cases of unregistered babies born to mothers of Korean nationality between 2015 and 2022. However, the vast majority of the “ghost babies” -- approximately 4,000 infants born to mothers of foreign nationality -- have so far been left out of the government’s investigation.

This decision came amid growing calls that the well-being of all “ghost babies” -- including those who were born to mothers of foreign nationality -- should be ensured, as without being registered, undocumented children do not have access to basic social welfare benefits such as health insurance and some forms of formal education.