The names of two of the four victims of the house fire at Puriri Street on Monday morning, 2 April, have been released.
Only two formal identifications and two post mortems have been completed.
They are;
Junichi TOMONAGA aged 58 years, male
Michiko TOMONAGA, mother of Junichi, aged 80 years
The other two identifications are expected tomorrow.
Detective Inspector Greg Williams says that the investigation has been upgraded to a murder inquiry.
"Our focus is to identify who is responsible for these deaths," he says.