A woman believed to be a family member of the two children whose remains were found in suitcases in New Zealand is in South Korea, Seoul police say.

The woman, a Korean-born New Zealander, arrived in South Korea in 2018 and there was no record of her departure since then, a police officer told Reuters.

Her whereabouts, and whether she had other relatives with her when she arrived in the country, were not immediately known.

“New Zealand police had requested confirmation whether the person who might be related to a crime case was in South Korea,” the police officer said, adding that given the woman’s past address and age, she could be the mother of the children.

New Zealand police launched a homicide inquiry in south Auckland this month after the remains of the children were found by a family going through the contents of a storage locker they had purchased unseen.

The children were aged between five and 10 years and had been dead for some time, New Zealand police said.

Detective Inspector Tofilau Faamanuia Vaaelua said last week the investigation was in its early stages but would be rigorous.

“This includes establishing where, when and how,” he said.

“It’s still very early stages of our investigation. We’re still on a fact-finding mission and we still have a lot of unanswered questions.”

The family who found the bodies were not connected to the deaths.

Prime Minister Jacinda Ardern was asked about the case in Wellington on Monday, and said she wanted to be cautious due to the ongoing investigation.

“I find any reporting that involves children very, very difficult. But I think everyone does,” she said.

-with AAP