Sept. 19 (UPI) -- More than 800 North Korean defectors are missing, or their whereabouts are unknown, according to Seoul.
The latest collection of data from South Korea's unification ministry indicates of the more than 30,000 North Koreans who have resettled in the South, a total of 886 defectors have disappeared, News 1 reported Tuesday.
The number of defectors whose address or contact information is no longer at the South Korean government's disposal has been creeping up slowly since 2013, when for the first time the number of missing defectors surpassed 800.
In 2014 and 2015, that number increased to 815, jumping to 888 in 2016 then 886 in July 2017.
The vast majority of the defectors could not be located because they had moved overseas.
In 2015, more than 80 percent of "missing" defectors, without a forwarding address, had gone abroad, with the rest remaining in the country, including some persons detained in South Korean prisons, according to lawmaker Park Joo-sun, the deputy national assembly speaker.
In its statement to South Korean parliament, the unification ministry stated there is currently no procedure requiring resettled North Koreans, who are naturalized South Korean citizens, to report their overseas address.
Only 53 North Koreans are registered as having immigrated on South Korean passports since 2014, the ministry said.
Cases of redefecting, or returning to the North after resettlement, are rare.
But that number is now up to five since 2013.
All five redefectors used a route that passes through China in order to return to their country of origin, according to Seoul.
The unification ministry said of the redefectors, four returned because they were "unable to socially adjust" to life in the South. One returned out of concern for family left behind.
All five defectors are charged with violating South Korea's anti-communist national security law. If apprehended, they could face a maximum 3-year, 6-month prison sentence.
Park said more should be done to address the difficulties in social adjustment defectors experience in their new country.