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WASHINGTON - It was a near-unimaginable Christmas Eve tragedy: three generations of a family, six people, shot to death at their home, apparently the dreadful climax of years of resentment by a daughter who felt ignored.
Most murder victims know their murderer.
But rarely has that old adage of crime been as savagely confirmed as in the killings of Wayne Anderson, 60, his wife Judy, 61, their son, Scott and his wife, Erica, and their children, Olivia and Nathan, aged six and three, at a rural property at the end of a dirt road in woods, 20 miles east of Seattle, near the small town of Carnation.
The slaughter, which the sheriff's office said was committed probably in late afternoon or early evening, was discovered only on Wednesday when a colleague of Judy Anderson, a postal worker, went to check after she failed to report to work.
He found the bodies scattered in and around the main house on the property, owned by Mr Anderson Snr.
After investigators arrived, the Andersons' elder daughter Michele and her boyfriend, Joseph McEnroe, 29, who lived in a trailer in the grounds, went to the house.
Within hours, they were under arrest.
Police said no motive had been found, and no murder weapon had been discovered, but a story was already emerging, of simmering family resentments, suspicions, and a quarrel over money, which seem to have boiled over into mass murder.
At the property, Ben Anderson, the Andersons' grandson and nephew of Michele, said there had been a long-running financial dispute between Michele and her parents.
His aunt, he told the Seattle Post-Intelligencer newspaper, had been at odds with them since she was 13 and was angry because she did not think her parents showed her enough love.
"She had a different way of thinking," Mr Anderson said.
"They had a lot of money. She had lived on the property rent-free her whole life, and they were just trying to help her out. But she felt she wasn't loved enough, that no one appreciated her, that she was pushed out of everyone's life."
In another twist, the sheriff's office said it had a 911 emergency call from the house at about 5.15pm on Christmas Eve.
Two deputies went to the property but left without entering when they found the gate locked.
The call, a police spokesman said, probably came near the end of the killings, though an exact timeline had not been established for each murder.
The emergency operator who took the call heard shouting in the background, but no voices.
"Heard a lot of yelling," the operator wrote in a note to the police dispatcher, but it "sounded more like party noise than angry heated arguing".
He made two more calls to the Anderson house, but each went to voicemail.
Half an hour later, the deputies reported: "Gate is locked; unable to gain access." Asked why they did not force entry, the spokes-man said: "I don't know why.
That's one of the things we're looking into."
- INDEPENDENT