Investigations are continuing to establish the cause of the Wednesday morning fire at Sage Restaurant and Cafe in Feilding.
Detective Constable Jane Borrie of Dannevirke Police said detectives and fire safety officers were working together and still had further people to talk to.
"Hopefully in a couple of days we will be able to ascertain the cause of the fire."
The restaurant destroyed by fire had been advertised as being on sale.
Owners Jay Wu and Nicol Li were too upset to talk about the blaze that destroyed their business yesterday.
The couple has owned the cafe/restaurant since 2009, and had been advertising the business for sale.
The building's owner Ken Cavanagh declined to comment on the cause of the fire until the investigation was completed, but said the building would be rebuilt.
"It is out of my hands now for about 6 to 8 weeks until the insurance company has finished their investigation. But it was fully insured."
A Feilding father and daughter were forced to flee for their lives after being awoken by the fire at the neighbouring cafe/restaurant.
The Sage Restaurant and Cafe on Feilding's Manchester Street was destroyed by a suspicious fire that started about 1am Wednesday.
Four fire crews from Feilding, Bunnythorpe and Palmerston North battled the blaze, which completely gutted the cafe and damaged neighbouring properties.
Feilding's Acting Fire Chief Gary Ward said when the first crew arrived the flames were through the roof.
He said there did not appear to be any activity near the front of the building but when the door was opened it ventilated the fire and revealed its intensity.
The fire damage spread to a neighbouring flat where father and daughter Daryl and Brooke Richardson were sleeping.
Roused from his slumber by ''popping and crackling'' noises, Mr Richardson said he initially thought his daughter was in the shower but then discovered the fire outside the window.
Mr Richardson woke up his daughter and the pair ran downstairs.
He told the Manawatu Standard he was feeling a huge sense of relief.
"Fire officers tell us, if we were heavy sleepers we wouldn't be alive," he said.
"As soon as we got outside the blaze was coming through the bathroom and lounge windows," Brooke Richardson said.
All of their possessions in the flat, which were uninsured, have been destroyed and the pair are looking for alternative accommodation in Feilding.
Firefighters saved neighbouring buildings from extensive damage, though some suffered smoke damage.
Fire walls and the effective response from emergency services was credited with containing the fire.
"We are very impressed with how crews worked to contain the fire," said Mr Ward. "With the intensity of the fire there was huge potential for it to spread. They have done a really good job."
Senior fire station officer Rob Freeman said the restaurant was badly damaged in the fire, which was well involved when crews arrived.
''It was a single storey property and the fire spread through the windows next door to a double storey property with a flat which had occupants inside,'' he said.
''It caused some damage to the flat. We are treating it as suspicious.''
Mr Ward said it does appear the fire started at the rear of the building and fire investigation teams are working at the site, alongside police.
- Manawatu Standard
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