In what is believed to be part of a wider campaign of hate and racism directed at the family, a Murray St shed was engulfed in flames on Monday evening.
The family, who for the last two and a-half years have been the victims of verbal abuse, harassment and racism, have lived in constant fear of what could come next.
Fenz Mosgiel Station Officer Scott Lanauze confirmed firefighters were of the view the fire was a criminal act.
"The investigation took place on the evening of the fire.
"The information available and the inspection of the scene leads to a classification of incendiary fire."
The family has had eggs thrown at them, rocks thrown at cars and through windows and their property has been damaged.
The Otago Daily Times asked police if they were treating the fire as a hate crime.
Detective Constable Shelley Dodds said the fire was being investigated as arson and police were continuing to investigate.
"As part of our investigation, we are working to determine the motivations of the incident.
"We understand the distress that incidents such as this can cause both the victim and community and we are working hard to identify those responsible."
After the incident first came to light, Dunedin Mayor Jules Radich said the Dunedin City Council was looking into what could be done to improve the safety of the family.
There were two main things that could be done, he said yesterday.
"Firstly, having the police involved to try and get to the bottom of what has happened.
"Secondly, get the community fired up for a bit of a wrap-around support."
Mr Radich, when asked about claims of the fire being a hate crime, said it was easy to jump to conclusions on the basis of what had been presented.
"I don’t want to be leaping to any conclusions based on one photograph."
Presbyterian Support Otago practice manager Debbie Gelling said her organisation would continue to provide support for the family.
The community was also planning for a street support party.
Community fundraising for the family had reached $13,885 last night.
