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A gentle autumn breeze rustles through the tree-lined driveway of the Schlaepfer family property in the rolling hills above Pukekohe.

A short distance away, a yellowed "shop hours" sign in a cobwebbed window is the only evidence that the shed it belongs to was once used as a farm vegetable store.

In the quiet, peaceful setting, just a 40-minute drive from inner-city Auckland, it is hard to believe that this is where the quiet, hard-working farmer who once owned the Paerata property "snapped" and killed six members of his family before turning a shotgun on himself 15 years ago.

On May 20, 1992, Brian Schlaepfer, 64, shot or stabbed the family, killing his wife Jocelyn, 55, his three sons, Peter, 39, Karl, 33, and Darrell, 31.

Also slain were Peter's wife Hazel, 42, and their son Aaron, 11.

As the tragedy unfolded Peter and Hazel Schlaepfer's 9-year-old daughter Linda waited, barricaded in a bedroom where for almost three hours she spoke, scared but calm, on a telephone to Constable Jeff Stuck at Auckland central police station.

Linda's sister Kerry, now a teacher, was away from the property and also survived.

Linda is still living in Paerata with her partner and is the mother of a one-year-old child.

She declined to speak to the Herald, saying through a family friend that she wanted to leave the events in the past.

Now a senior constable based at Papakura as a prison escort officer, Jeff Stuck also refused to talk about the case, saying it was "done and dusted".

He did express surprise that it had been 15 years since the tragedy and said he had not had contact with the survivors.

The officer in charge of the case, then Detective Inspector Kelvin McMinn, described an anxious wait on Ostrich Farm Rd that day, as armed police stormed the property, hunting a gunman gone mad but who had already killed himself.

Mr McMinn, then acting district commander of Papakura, said the case was one he often thought about since retiring in 1997 after 28 years' service.

"It would be one of the cases that does stand out quite a lot in my mind given the nature of the terrible events that happened that day and the multiple deaths that occurred," Mr McMinn said.

"It was perhaps one of the more intense days of my career."

The motive for the mass killing was never totally clear but Mr Schlaepfer suffered from depression in the lead-up to the slayings and had refused help. Whatever the reason, a reminder of the tragedy can be seen about 2km from the site, at Heights Park Cemetery, where headstones mark the graves of the killer and his victims.

DAUGHTER'S THREE-HOUR NIGHTMARE

"MY granddad ... he's shot my brother ... and I think he's coming to shoot me."

These were the words of 9-year-old Linda Schlaepfer to a police officer after having dialled 111 from the room in which she had barricaded herself as her grandfather went on a stabbing and shooting rampage.

Only moments earlier, the child had listened to her 11-year-old brother plead for his life before hearing the gunshot that killed him.

The conversation with Constable Jeff Stuck - who was at a central Auckland 111 call centre - lasted almost three hours.

It began as Linda clutched the phone that her mother Hazel had dropped as she died, having desperately called for help just minutes earlier.

Hazel was shot while Mr Stuck sat helplessly listening. There was a two-minute silence between the gunshot and hearing Linda's voice.

"He shot her up her nose ... she's just lying there," Linda told Mr Stuck as she sat beside her dead mother.

Linda calmly guided police to the property where her mother, father, older brother, two uncles and grandmother died at the hands of her grandfather, who then turned a shotgun on himself.