A witness has detailed the scale of a fatal house fire in South Auckland's Hillpark, near Manurewa, just before 7am

Two people died and one person has serious injuries.

Local, Jonathan Asafo, says he was driving to drop his child at daycare, when he saw the house's bottom floor was engulfed in flames.

He says he started beeping his horn to alert people, and found the survivor outside.

Asafo says he could see the all the furniture, window frames and doors melting off, and flames coming out.