Counties Manukau Police are considering further charges after more information was gathered following the exhumation of a baby's body.
The five-month-old baby girl, whose name is suppressed, died in Pukekohe in August.
Troy Solomon has been charged with the girl's murder and is due to stand trial next year.
Detective Inspector Dave Lynch said the scope of the investigation has now broadened as more serious historical injuries were identified on the girl.
He said exhuming the body was very distressing for the family and local iwi but it was crucial for the investigation.