Police reveal what went wrong in tragic triple-fatal farm accident

Emergency services were called to the property just after 11am on Sunday.
Emergency services were called to the property just after 11am on Sunday. Photo credit: File / Getty

Police have revealed more details about what took place in a tragic farm accident near Raetihi on Sunday. 

A 66-year-old woman and her two grandchildren, boys aged five and 10, died in the incident, after the side-by-side off-road vehicle they were in crashed into a farm pond.

Police said they were called to the property in the Ruapehū district, just after 11am after the vehicle crashed into a dam.

Four people were riding in the vehicle when it crashed, however a 69-year-old man - understood to be the boys' grandfather - managed to free himself. 

The remaining three people were unable to get out of the vehicle and had already passed away by the time emergency services pulled them out of the pond.

The surviving man was taken to Whanganui Hospital by helicopter with moderate injuries.

All those involved belonged to the same family, police said.

Ruapehu Mayor Don Cameron told RNZ the incident was an "absolute tragedy" for the community.

"One member of the family had left his work when he heard something had happened and he had jumped off to a digger which was parked nearby, rode it down and went to the dam to block the water levels so he could get to the vehicle," Cameron told Morning Report.

The water in the pond was roughly 3-4 metres deep, he said.

The principal of Ohakune Primary confirmed two of its students had died in the incident, according to NZME.

Enquiries into the circumstances leading to the crash are ongoing and police and victim support are providing assistance to family members.