Hamberger said damage to the charity shop’s building, shop and stock was significant.
The neighbouring bakery escaped serious damage, but a 90kg gas bottle at the rear of the building was on fire, putting the business out of action.
Fire investigator Graeme Matthews said inquiries were continuing.
“We’ve got a bit more work to do to wrap up the investigation, but at this stage, we’re treating it as potentially suspicious.”
Matthews said the fire started at the back of the building and went up into the roof space.
He said it was a blow to the young family that had bought the bakery just two months ago.
They had since had an electrician, gas fitter and refrigeration technician in to carry out repairs.
In a social media post, the Kerikeri Bakehouse and Cafe owners said the business would reopen from 7am Monday, and thanked customers for their patience and support.
The Salvation Army store has been boarded up and will need major repairs.
– RNZ