Police believe Coral-Ellen Burrows died soon after going missing after being dropped at her primary school on Tuesday last week.
An autopsy was held in Wellington yesterday afternoon to determine when and how she died.
"Every indication is that she has been dead since very shortly after she went missing," inquiry head
Detective Inspector Rod Drew told a press conference held after her stepfather, Steven Williams, appeared in court on a charge of murdering her.
"The post mortem will determine exactly what the cause of death was."
Coral's body was found on the shores of Lake Onoke (Lake Ferry), near the Ruamahanga River mouth.
It was found in what appeared to be a maimai (a duck-hunting hide), "but it's really just a gap in between two big clumps of toetoe", Mr Drew said.
He confirmed the area had not previously been searched by police, but said reports of vehicles police were interested in near that location would have soon led police to the scene.
"It's a dreadful investigation to be involved in, but it's certainly very satisfying to solve it. At the same time, we have strong feelings for the situation the family is in," Mr Drew said.
"The tragic death of a young child is always particularly hard, but I know the level of public support is providing some support to Coral's family."
Mr Drew said police still had a great deal of investigative work to do on the inquiry.
He paid tribute to police and the Featherston community for their contribution to the inquiry.
"The support of police and civilian search volunteers ... and from people in the local community who have provided food, accommodation and messages and other goodwill, has been absolutely phenomenal and has kept the investigation team buoyed and working hard."
- NZPA
