The fire which gutted a popular Indian restaurant in North Dunedin has been found to have originated in a counter where poorly stored wires and charging electrical devices were kept.

The blaze happened early in the morning of April 4, extensively damaging the interior of the Taj Mahal Indian Restaurant in George St.

The restaurant was a popular venue with students and has remained closed since the fire, which was first reported at 3.12am by the driver of a passing truck who saw black smoke streaming out of the building.

The first appliance arrived five minutes later and firefighters broke down the front door to extinguish the fire, which was concentrated in the reception area between the dining area and kitchen.

Fire and Emergency New Zealand specialist fire investigator Scott Cameron completed the investigation into the cause of the fire.

His report found the fire had started in the shelves under the reception counter, where the intensity of the fire had burnt most of the electrical devices and wiring which had been there.

There had been a Menulog device, a multibox, a modem and a pair of tablets which were on charge there, but the devices were so badly damaged in the blaze that a specific origin point could not be identified.

The was a lot of wiring found in the vicinity of the counter which was "not stored or maintained well" with some wires being bent, poorly stored or having heavy items lying across sections of them.

Information provided after initial investigation found the Menulog device failed an electrical test conducted after the fire, which could have been a factor in sparking the blaze, the report said.

The restaurant itself was described as "untidy and cluttered" but with no sign of rodents which might have sparked a fire by chewing through cables.

The fire caused severe damage to the business' interior, with damage to a flight of stairs above the reception area and burnt furniture in the dining area, where the glass door of a drinks fridge shattered in the high temperatures.

The upper floor of the building, used for storage, escaped unscathed but the kitchen was left covered in soot and stained from smoke, with melted light fittings.

The fire was ultimately recorded as an "accidental electrical event", the report said.