A 4-year-old boy has died after being hit by a light truck in rural South Auckland last night.

St John Ambulance spokeswoman said the boy was taken to Starship Hospital in a serious condition, with a police sergeant stepping in to drive the ambulance as the paramedics worked on the boy.

However, he later succumbed to injuries and died, police said.

Police communications shift commander Inspector Ian Brooker said the incident did not appear to be a hit-and-run.

"I don't think it was a driveway thing, but it doesn't sound like high-speed either."

The incident occurred just after 8pm in Union Rd, Pukekohe.

There were a lot of people present at the crash site when police arrived on the scene, Mr Brooker said.

The incident would be investigated by the police serious crash unit.

The driver of the truck was assisting police with their enquiries.

- APNZ