The road is currently closed, and motorists are advised to avoid the area if possible and follow diversions.
Hato Hone St John said it received a call at 8:23pm to a motor vehicle incident in Kumeū.
Four ambulances, five rapid response units, two operations managers and one Major Incident Support Team unit responded to the scene.
Ambulance officers treated and transported four patients to Auckland City Hospital.
Two are in critical condition, and two are in serious condition.
Fire and Emergency New Zealand said it received reports of the incident at 8:23pm this evening.
No persons are trapped and no structural damage was made to the house, Fire and Emergency NZ said.
Two fire trucks are currently in attendance.
More to come.
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