bought by family at auction in New Zealand

A homicide investigation is underway after the remains of two children were discovered in suitcases bought by family at auction, police in New Zealand announced Thursday.

In a statement, police said they were alerted to the case last week when the family from the South Auckland suburb of Manurewa reported finding human body parts in several items they bought from a storage facility.

"Initial post-mortem examinations have been carried out and the results show that the remains found in two suitcases are that of two primary school-aged children," according to the statement from police spokesperson Anna Thompson.

The children — likely between age 5 and 10 — may have been dead for a number of years, police Detective Inspector Tofilau Faamanuia Vaaelua said during a news conference Thursday.

Once the children are formally identified, authorities said their top priority will be to notify the victims' next of kin.

We want to reassure the community our investigation is continuing to establish the facts to ascertain the full circumstances around the deaths of these children," the statement continues. "This includes establishing when, where, and how."

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Police said they are working with Interpol and have opened inquiries with overseas agencies, but initial inquiries suggest relatives of the victims are in New Zealand.

The family who found the remains is not tied to the victims' deaths, police said, and are "understandably distressed."

Natalie Neysa Alund covers trending news for USA TODAY. Reach her at nalund@usatoday.com and follow her on Twitter @nataliealund.

This article originally appeared on USA TODAY: Remains of two kids found in suitcases bought at New Zealand auction