Police say a post-mortem has revealed the 10-year-old Levin boy Alex Fisher suffered head trauma.
A three-day search ended on Thursday when the body of the 10-year-old was discovered in dunes at Waitarere Beach.
Police have set up an information hotline as they continue their homicide investigation into Alex Fisher's death and said they had received a reasonable response.
Detective Senior Sergeant Neil Forlong said there may still be unreported sightings of Alex or his older brother Eric early last week.
He said the police would also like to hear from anyone who thought their property has been interfered with, or who had items missing.
The number to call is 0800 234 7437.
Mayor of the Horowhenua District Brendan Duffy said he called in on the Fisher family this morning and they were focussed on getting the boy's body back.
He said it was an enormous challenge for the family.
"It's raw, the emotion is, you know it's pretty tough for them, they're preparing at some stage over the weekend for Alex to come home - I don't know when exactly that will be. They're a family that is uncomfortable, very uncomfortable in the public spotlight and are finding that extraordinarily challenging."
Mr Duffy said the community in the small village of Waitarere was struggling to cope and a candlelight vigil tomorrow night would act as therapy for many.
Trauma specialists from the Ministry of Education will be on hand at Alex Fisher's school on Monday as children return from holiday.
A ministry team has already met with all staff at Ohau School to advise them on how pupils may be responding and how to get psychological support.
The community will come together for a thanksgiving vigil in the Waitarere Domain on Sunday evening to support Alex's family and friends.