Fatal fight started over laundry
Man shoots wife and two others before he is killed by son
The row was apparently over a washing machine.
But the fight spun out of control and left four people dead.
A 54-year-old man shot and killed his wife and two others in his home in California, Fox News reported.
In a dramatic twist to the shooting on New Year's Eve, the man's son, Christopher Morey, snatched the gun and fatally shot him.
"It looks like it was a dispute between the dad and the son's girlfriend, probably over using the washing machine," Sheriff's Lieutenant John Corina told the San Gabriel Valley Tribune.
The 54-year-old was a heavy drinker with a large gun collection, and authorities had made dozens of previous trips to the home, the Los Angeles Sheriff's Department said.
Christopher Morey, 33, was held on suspicion of murder and bail set at US$1 million (S$1.4 million).
His girlfriend and Mr Ernesto Calzadilla, a 27-year-old man who was visiting at that time, are among the dead.
Lt Corina told The Los Angeles Times that investigators were still trying to determine why the father started shooting, but said those in the group "were all drinking".
He said investigators were looking into whether the shooting stemmed from a dispute earlier in the day between Morey's father and Morey's girlfriend over her use of a washing machine.
A friend of Morey's was quoted saying that the suspect went crazy after his girlfriend was shot.
Neighbours said the family was friendly and had barbecues in the yard, but they drank frequently and could sometimes be loud.
Bottles of beer were stacked on shelves near the front door of the house, filling a laundry basket and cardboard box.
Those who knew the suspect and his father said the two cared for Morey's mother, bedridden after suffering a series of strokes.
The father worked long hours, they said, and caring for the mother took its toll on both men.
"They had to do everything for her," said Mr Sean Tubbs, 27, who grew up with the suspect.
Mr Tubbs and others said the father was not particularly welcoming toward guests.
Another family friend said he always carried a gun.
Mr Calzadilla's brother said the father had pulled a gun on the victim many times, even shooting at him once.
Mr Calzadilla had just been hired by a warehouse after losing his previous job.
He leaves behind an eight-month-old daughter.