The neighbour described the children at the home as “happy, sweet kids”.
Manawatū Area Commander Inspector Ross Grantham announced the deaths in a statement.
“Police can confirm there have been several fatalities at the scene of a house fire in Sanson today.
“Emergency services were called to the property southwest of the town about 2.30pm.
“Fire and Emergency NZ have now handed the scene to Police, who will commence an investigation phase in relation to the circumstances of the fire.
“Police can confirm we are not seeking anyone else in relation to the fire”.
A police scene guard will remain in place overnight, with officers to return tomorrow.
The large blaze has closed SH1 between Phillips St and Speedy Rd, police said earlier.
Firefighters from the Bulls, Rongotea, Manawatū, Whanganui, Marton and Palmerston North brigades have been called to the serious incident.
Fire and Emergency New Zealand declined to comment when approached by the Herald.
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