About 4pm the Duntroon Volunteer Fire Brigade was called to the alleged arson in a paddock in Livingstone St.
Duntroon Chief Fire Officer David Eckhardt said a ute and trailer had been parked on the yellow lines outside the Rees St station, blocking the fire engine's exit.
The driver emerged from a nearby house and ''eventually'' moved his vehicle after words were exchanged, Mr Eckhardt said.
Constable Craig Bennett, of Kurow, said he was following positive lines of inquiry, receiving reports of sightings of that person in the area when the fire was started.
About a hectare of land was burnt.
The fire also damaged telephone lines and spread to the Maerewhenua river bed, setting alight old logs and debris.
The Duntroon Volunteer Fire Brigade was assisted by Kurow and Waitaki Rural Volunteer Fire Brigades and seven appliances attended.
They took about five hours to get the fire under control, and continued to monitor it yesterday.
Although the fire did not pose a threat to livestock, buildings or people, it was an ''annoying'' case of arson, Waitaki Rural Volunteer Fire Brigade Deputy Chief Fire Officer Eric Spittal said.
''A frustrating fire that was deliberately lit and caused a lot of work for volunteers and police,'' Mr Spittal said.
