A fire in a central Dunedin building overnight is being treated as suspicious.

Crews were called to the blaze, in a building on High St, about 2.40am on Friday, a Fire and Emergency New Zealand spokesman said.

The fire had taken hold in the rear of the building, but firefighters were able to extinguish it quickly, he said.

There were no reports of injury.

The extent of any damage was not known, but the blaze had been “flagged as suspicious”, and a fire investigator would be called in, he said.

— Allied Media