Last week, New Zealand police said they found the bodies of two children between the ages of 5 and 10 in suitcases.
The discovery was made when a family bought a trailer loaded with bulk goods at a warehouse.
New Zealand police say the bodies may have been stored for years, making investigations difficult.
South Korean police said a woman who is a relative of the children born in South Korea is currently in the country.
“We can confirm that he is in South Korea and that he is a New Zealand citizen of Korean descent,” a South Korean police official told AFP.
The woman arrived in South Korea in 2018 and there is no sign of her leaving the country since then, he added.
“The New Zealand Police are conducting this investigation and we intend to cooperate with their request,” he said.
Police are examining hours of surveillance camera footage, but the long delay between the deaths and the discovery of the bodies may have erased key moments.
Forensic scientists thoroughly examined the warehouse and property where the bags were located.
New Zealand officials reiterated last week that the family behind the discovery was not connected to the two children’s deaths and may have received help dealing with the trauma.
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