A nearby police officer desperately tried to revive a child in a South Auckland driveway but the 1-year-old tragically died at the scene.
Police launched a homicide probe after the infant died in the suburb of Clover Park on Saturday night.
Flat Bush Rd resident Albert Vahaakolo said he had seen police further up the road that night responding to a separate incident, before somebody called out to police for help.
An officer had only been roughly 50 metres or so away and was able to get to the house quickly.
The police officer started CPR in the driveway, hunched over in the driveway facing the house, he said.