The family's troubles were laid out in family court documents dating back to August 2011.
In a fit of rage last summer, his father alleged, Grigoriy Bukhantsov hurled furniture, struck his father with such force that he fell, and threatened to kill every member of his family "like Soltys did."
It was Aug. 9, 2011, according to allegations documented in family court files, when Bukhantsov reportedly made the haunting reference to Sacramento serial killer Nikolay Soltys, who in 2001 stabbed six family members to death, including his pregnant wife and 3-year-old son.
Fourteen months after the statements were documented, Sacramento County sheriff's detectives say Bukhantsov followed through on his threats, leaving his sister-in-law and young niece and nephew dead in a bloody attack in a Rancho Cordova duplex Tuesday afternoon.
Early Wednesday, deputies arrested Bukhantsov on suspicion of three counts of murder. In the following hours, a troubling picture emerged of the 19-year-old's past.
Sheriff's officials have not said how 23-year-old Alina Bukhantsov and her children 3-year-old Emmanuela and 2-year-old Avenir were killed, only that their injuries were "consistent with sharp-force trauma."
Their bodies were found by Denis Bukhantsov, Alina's husband and father to the toddlers. After he summoned help to the family's De Soto Way home, sheriff's deputies found the couple's youngest child, a 6-month-old boy, crying but unharmed in a back room.
Detectives took an interest in Grigoriy Bukhantsov early in the investigation, and alerted local law enforcement to keep an eye out for the victims' stolen minivan, said sheriff's spokesman Sgt. Jason Ramos.
About 2 a.m., Rocklin police officers spotted the van outside a Denny's and called the Sheriff's Department. Deputies pulled Bukhantsov from a booth inside where he was sleeping, Ramos said.
Bukhantsov was booked into the Sacramento County Main Jail about 6 a.m. Later Wednesday, he was being held on the jail's psychiatric floor, and declined interviews with the media.
"We can't talk about the motive for sure, but we have found there were strained relationships in the family," Ramos said. "What the catalyst may have been for (Tuesday's) horror, we don't know yet."
Restraining order was sought
Court documents and interviews indicate the young man began acting out at least three years ago.
Florin Ciuriuc, executive director of Sacramento's Slavic Community Center, said he has known Grigoriy for years. Ciuriuc described him as a sweet boy who transformed into a problematic high school dropout.
The Bukhantsov family came to the United States as religious refugees from Ukraine and were devoted members of the Bethany Slavic Missionary Church, the nation's largest Russian-speaking congregation, with 10,000 members. Grigoriy's father, Aleksey Bukhantsov, worked as a beekeeper.
Leaders of the region's Slavic community have counseled the family over the past three years on dealing with Grigoriy's behavior, Ciuriuc said.
In August 2011, Aleksey Bukhantsov went to family court and applied for a restraining order against Grigoriy, court records show. He asked that the order protect himself, his wife and 11 other family members, including Denis, Alina and their children.
In the application and with the help of a translator, Aleksey Bukhantsov described three recent confrontations in which Grigoriy allegedly was violent with family members and threatened to kill them, according to the court file.
In one instance, the father wrote, Grigoriy "threatened to have his friends come and block all exits and set the house on fire while everyone is sleeping."
The court granted a temporary restraining order. But at a hearing two weeks later, the matter was dropped at the request of the court. Records do not indicate a reason.
Last December, Grigoriy Bukhantsov was arrested on suspicion of breaking into a home in Sacramento County. He pleaded no contest to a felony count of burglary and was sentenced to a year in jail; he was released after a few months.
Bukhantsov remains on formal probation, and was scheduled to appear in court Halloween day for an alleged violation that is not detailed in court records.
About six months ago, after Bukhantsov's release from jail, Ciuriuc said he joined Bishop Adam Bondaruk, pastor of Bethany Slavic church, in a visit to Bukhantsov's parents' home in Carmichael.
"Pastor Bondaruk said, 'Grigoriy, you're a young kid, everybody makes mistakes. My kids make mistakes. We go through all kinds of ordeals,' " Ciuriuc recalled of the meeting. "'You have to put a stop to it.'"
But Grigoriy jumped up and made statements that frightened the group, Ciuriuc said.
"It was just like the devil got into him," he said. "His father, a very kind, calm person, was crying."
Ultimately, Aleksey Bukhantsov, his wife and their youngest son left their home in Carmichael for Missouri, according to Ciuriuc.
Reached at their new home by phone Wednesday, the family, through the son, declined to comment.
After they left, Grigoriy asked church leaders for bus money to follow his parents and was denied. Then he began visiting Denis and his family "like nothing had happened sleeping on their couch, opening their refrigerator," Ciuriuc said.
Ramos, the sheriff's spokesman, said Grigoriy Bukhantsov had no permanent address and appears to have been staying with friends and family, and at some point with Denis and Alina.
Pavel Tsymbal said Grigoriy briefly stayed with him after being released from jail, but the arrangement ended about a month ago.
"I was taking him to church with us, but he didn't want to change," Tsymbal said. "I saw him like a week ago, and his eyes looked crazy."
Couple met on church mission
By Wednesday afternoon, De Soto Way was once again quiet. The police tape came down, almost 24 hours after it was strung up. Parents walked the street with children. Neighbors boarded up a hole in the garage door of the family's duplex that firefighters had made as deputies searched the home for bodies.
But peace evaded friends and family of Denis and Alina Bukhantsov.
According to friends, Alina came to the United States in 1998 from Belarus. She met Denis on a church missionary trip, and the two were wed at Bethany Slavic church in 2008.
Before being laid off in 2009, Denis worked as a draftsman at Macauley Architects in Sacramento, according to Robin Bettencourt, a financial officer in the firm who attended the couple's wedding.
After he lost his job, Denis stayed home with the children while Alina went to school, Bettencourt said. Last year, Alina graduated from California State University, Sacramento, with a degree in child development, according to her friend Luba Petrashishin.
At that point, Denis returned to school, Bettencourt said, studying engineering and design technology at American River College.
Petrashishin, 23, said she has been close with Alina since they attended Mills Middle School together. She described her friend as a dedicated wife and mother who considered all her children "blessings."
She said the couple were strong in their faith, with Denis serving as a preacher at Bethany Slavic and Alina as a Sunday school teacher.
"They were the couple you look up to," she said. "They were perfect."
A day after Alina's death, Petrashishin said the news still seemed unreal. She could not reconcile how something so ugly could happen to someone so loving.
"You just want to be around people like that," she said. "That's why I don't understand."