She claimed there had been arguing between a man and a woman shortly before the shooting, "but we couldn't make out what was said".
"After the shots, we heard a distressed woman's voice yelling, 'What the f***' over and over again.
"A little too close for comfort but looking like another shooting in West Auckland."
Another witness said a cordon was in place on Newington Rd with an armed guard stationed outside a house.
At least seven police vehicles were on the scene as well as an ambulance crew.
The man said a Fire and Emergency lighting unit and police photographer had since arrived at the fatal shooting. A tent was being set up outside the address.
He also saw at least a dozen police vehicles speeding towards Te Atatū Peninsula just after 9pm.
"There were dog handlers, marked and unmarked cars, and also the Eagle helicopter."
The shooting is the latest in a worsening spate of gun violence across the city.
In recent months a series of tit-for-tat drive-by shootings have terrorised residents in West and South Auckland as tensions between rival gangs the Killer Beez and Tribesmen flared.