Police cordoned off Jack's Point Rise after the girl was struck by a black Subaru station wagon driven by a woman, about 11.15am, while walking with her mother.
Police were unable to provide an update on the girl's condition yesterday.
Detective Grant Miller, of Queenstown, said he could not comment on what led to the collision because police were "still trying to piece that together".
The girl's injuries were serious, he said.
The incident happened in a quiet residential area, on a long stretch of road.