Investigators are piecing together what caused a helicopter crash near the Snowy Mountains in NSW that killed a man and woman from Sydney’s north.

Emergency responders found the wreckage in the sparsely populated Kiandra Flats just before midnight on Monday, NSW Police said.

The pilot and the passenger suffered fatal injuries and died at the scene.

The victims of the crash were a 64-year-old woman and a 75-year-old man from Sydney’s northern suburbs, Monaro Police District Commander Superintendent John Klepczarek said.

“Very little is known about the helicopter and the occupants.”

Police believe the helicopter landed safely in the area on Sunday afternoon due to weather before the crash late on Monday night.

“We’re [starting] this investigation virtually from scratch. We’re piecing back, from what we know last night, basically backwards,” Commander Superintendent Klepczarek said.

The pair were found dead by rescuers, and the helicopter, which was privately owned, was destroyed in the crash, Commissioner of the Australian Transport Safety Bureau Angus Mitchell said.

A request for help was sent to the Australian Maritime Safety Authority Joint Rescue Coordination Centre after the Bell LongRanger helicopter was last tracked.

It was later located by rescuers about 200 metres east of the Snowy Mountains Highway.

A crime scene was established by Riverina Police. Police remained at the scene on Monday afternoon.

An investigation into the crash has also been launched by the ATSB, Mr Mitchell said.

Five transport safety investigators with expertise in aircraft operations and maintenance, aerospace engineering, and human factors are preparing to travel to the crash site.

The investigation will include evidence collection, site mapping, retrieval of the wreckage, weather analysis and interviewing any witnesses to the crash.

A report will be released at the conclusion of the investigation in six to eight weeks.

It is the second fatal helicopter crash in Australia in less than a week.

A pilot and four passengers died last Thursday when their helicopter came down at Mount Disappointment north of Melbourne in Victoria.

– AAP