Hato Hone St John sent two vehicles to the fire, where they began administering medical treatment to two individuals at the scene.
One person was transported to Middlemore Hospital in a serious condition, while another was treated by Hato Hone St John at the address of the affected structure.
Fire and Emergency said the fire has since been suppressed, and crew are actively “monitoring the situation”.
In an update at 3:30pm, Fire and Emergency said investigators have wrapped up work.
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