The small community of Lockhart in the NSW Riverina has been left devastated following the shooting deaths of a "much-loved" mother and her three young children, police say, as their investigation turns to finding the missing father.

Police divers were on their way to the property Watch Hill, west of Wagga Wagga, on Wednesday morning to begin searching the dam for Geoff Hunt, 44, who has not been seen since the bodies of his wife Kim, 41, son Fletcher, 10, and daughters Mia, 8, and Phoebe, 6, were found on Tuesday afternoon.

Superintendent Bob Noble, the commander of the Wagga Wagga local area command, said all four victims had gunshot wounds, but police were yet to find the gun.

He said police would scour the large property for Mr Hunt on Wednesday, focusing particularly on the dam and its surrounds, after a white ute was found near the dam.

Superintendent Noble said it was important not to jump to any conclusions.

"We're making no assumptions because we just don't want to rule anything in or out," Superintendent Noble said.

"But obviously if there's anyone out there that might have any information that can assist in any regard, particularly if they've got any information about where that gentleman [Mr Hunt] might be, they ought to ring us."

Superintendent Noble said the Hunt family was well known in the area, and the community was struggling to come to terms with such a loss. All three children attended St Joseph's School, a primary school in Lockhart.

"You can only but imagine what that's going to do to that little school," Superintendent Noble said.

"These people [the Hunts] were well integrated with their local community, through work, through social events, through sport, three young children that attended the local school.

"They were obviously productive members of the community. It is going to devastate everyone, from the little kids in the community, to the community leaders, the old folks, and their network of friends and family throughout the state. They were well integrated and well loved ..."

He said the extended Hunt family was "not coping very well at all".

Fairfax Media understands concerns were raised when the children failed to turn up to school.

It is believed a concerned woman went to the property on Boree Creek Road, 13 kilometres from Lockhart, and discovered the grisly scene about 3pm on Tuesday.

Police later found a suicide note at the property. Investigators have not disclosed who the note was from.

Superintendent Noble said those who arrived at the home discovered a "horrific scene".

The children were found inside the house while Mrs Hunt's body was found on the footpath behind their homestead.

"The member of the public that dialled triple-0 and the ambulance officers and the police that attended were met with a horrific scene," he said.

"At any rate, with that in mind, while we've got to focus on the investigation, on examining the crime scene and locating this outstanding person, we have a focus as members of the community to look after that community that are devastated and will continue to be so no doubt for a long time to come."

He could not say whether the Hunts and their farm were under an unusual amount of financial strain.

"There's no doubt life on the land's very difficult," he said.

"In certain parts of the country at present, it's very hard on people, but I can't comment as to whether that was a stressor in this particular matter."

A family friend said Mr Hunt had been a pillar of support for his wife as she recovered from serious injuries when her car flipped twice on Boree Creek Road in 2012.

Their daughter Phoebe, aged four at the time, was also in the vehicle but suffered only minor injuries.

But Mrs Hunt, a nurse, was left with a broken neck, seven weeks of post-traumatic amnesia and a brain injury.

"He was very supportive in the months after her serious accident," the friend said after learning of the deaths.

"He really looked after her," she said.

Last year the family spoke to The Daily Advertiser about Mrs Hunt's slow recovery, and Mr Hunt praised his wife's resolve.

"The past year has had its ups and downs," he said.

"But you don't get much more determined than Kim, she's one of a kind."

Strike Force Tullaroan has been formed to investigate the deaths. It comprises officers from the Wagga Wagga local area command and the State Crime Command's Homicide Squad.

Superintendent Noble said police would search the farm on foot, while divers would focus on the dam and the PolAir helicopter would search the property from the air.

Bad weather in the area on Tuesday night had hampered the initial search, he said.

Police have urged anyone with information about Mr Hunt's location to contact Crime Stoppers on 1800 333 000 or use the Crime Stoppers online reporting page.

- with Emma Partridge and Patrick Begley

❏ Support is available for those who may be distressed by phoning Lifeline 13 11 14; Mensline 1300 789 978; Kids Helpline 1800 551 800.