Wipari Henwood, District Manager Northland, Fire and Emergency said the fire has spread due to weather conditions.
"The fire has spread faster than anticipated due to the weather conditions and there is a risk to the township of Kaimaumau overnight. As the wind drops and temperate cools at night, it should slow the fire down," he said.
"We will continue to monitor the situation overnight and the priorities from first light will be to reinforce a containment line around the township with heavy machinery, and protect the properties."
The fire is on Department of Conservation land. On Sunday around 20 firefighters, along with seven helicopters, were deployed to contain it.
Henwood said crews from Whangarei and Kaitaia specialising in structure protection would join the existing ground crews, along with nine helicopters.
Northern Fire Communications shift manager Kaisey Cook said on Monday morning that the fire was partially contained but still burning.
A further eight helicopters will return to the air at first light using monsoon buckets to pick up and dump water on the scrub fire.
Nearby areas Awanui and Karikari Peninsula are in a year-round restricted fire season, meaning a permit is required to light a fire in the open.