A ringing alarm system and passing police officers kept fire damage to a Northland school to a minimum early yesterday.
An electrical light fault  outside  a classroom at Dargaville High School is thought to have sparked a fire that  spread into the roof cavity and set off a smoke alarm about 3am.
Northland fire safety investigator Craig Bain believed moisture had accumulated in the light,  after heavy rain in Dargaville on Saturday, and a fault had developed.
The alarm system  had activated and a passing police patrol had  gone to investigate. Officers  had phoned the Fire Service,  which then sent  Dargaville volunteer firefighters to the school.
"There were a whole lot of factors that happened which meant the damage was kept to a minimum," Mr Bain said.
The outside of the weatherboard classroom and the ceiling cavity had been damaged.