New Zealand police said last week that they had found the bodies of two children, aged 5 and 10, in two bags.
The discovery was made when a family purchased a trailer loaded with items sold in bulk at a warehouse.
New Zealand police said the bodies were likely stored for several years, making the investigation difficult.
South Korean police said a woman, possibly a relative of the children, who was born in South Korea, is currently in the country.
“We can confirm that she is in South Korea and that she is a New Zealand citizen of Korean origin,” a South Korean police official told AFP.
He added that the woman arrived in South Korea in 2018, and there is no indication that she has left the country since then.
“New Zealand police are conducting this investigation and we intend to cooperate with their requests,” he said.
Police review hours of CCTV footage, but key moments may have been erased by the long delay between the deaths and the discovery of the bodies.
The warehouse and the property where the bags were located were thoroughly examined by forensic scientists.
New Zealand authorities confirmed last week that the family behind the discovery had nothing to do with the deaths of the two children and may have received help dealing with the trauma.
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