Authorities in Sacramento, Calif., arrested a 19-year-old man Wednesday in connection with the brutal slaying of his brother’s wife and two young children Tuesday night.

Deputies with the Sacramento County Sheriff’s Department took Grigoriy Bukhantsov into custody at around 2 a.m. Wednesday after they found him asleep at a Denny’s restaurant in Placer County. 

On Tuesday, Bukhantsov’s brother found the bodies of his wife, his 2-year-old son and his 3-year-old daughter when he returned to the family’s Rancho Cordova home, about 15 miles east of Sacramento. He then ran to a neighbor’s home and called police.

"It was very clear the victims obviously met a very violent end," sheriff’s department spokesman Sgt. Jason Ramos told NBC News. "They all sustained injuries consistent with blunt-force trauma and they were all in close proximity to one another. Indications are that this was a swift attack but very violent." 

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A 6-month-old baby was found unharmed and taken from a different room of the house to be with relatives, police said.

Authorities had been searching for a 2005 Chrysler minivan that had been stolen from the family’s home after the attack and spotted it outside the restaurant.

There, they found Bukhantsov asleep in a booth with a plate of chicken-fried steak with gravy, the San Jose Mercury News reported. He was taken into custody, booked and interviewed.

“Based on that interview as well as what we have learned throughout the investigation since yesterday afternoon, we have arrested him for the murders of all three victims,” Ramos said. “We believe he is the only person responsible for this. We’re not looking for any outstanding suspects at this time.”

Police said Bukhantsov's brother is cooperating with the investigation, despite being distraught.

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Ramos described the manner of the attack as a "stabbing" and "slashing," but declined to go into further detail pending a coroner’s inquiry.

"[Bukhantsov] had strange relationships with other members of the family, something bad was brewing for some time,” Ramos said. “This is somebody who confronted a family inside their homes and took their lives very violently,” Ramos said. “It’s shocking, even to veteran law enforcement.”

The identities of the victims were not immediately released.

Authorities also have not identified the brother but California Department of Motor Vehicle records show Aleksey Bukhantsov was the registered owner of the 2005 Chrysler minivan, according to The Associated Press.

The AP also says Grigoriy Bukhantsov was “somewhat nomadic, living temporarily with various family members and may have even stayed with his brother’s family in the duplex where they lived.”

Bukhantsov is currently being held without bail at the Sacramento County Jail. He is scheduled to appear in court on Friday afternoon. 

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Courtesy Lomax family

Linnea Lomax, 19, was last seen on June 26, 2012.

Updated 12:30 p.m. ET Saturday: A body discovered in Sacramento has been positively identified as 19-year-old Linnea Lomax, a distraught University of California, Davis freshman reported missing in June.

The Sacramento County coroner's office, which confirmed the body’s identity, said Lomax's death is under investigation, but foul play does not appear to be a factor, NBC television station KCRA reported.

The badly decomposed body was discovered 10:18 a.m. Friday near the shore of the American River by volunteers organized by the Klaaskids Foundation. It was in the Glenn Hall Park area, not far from where Lomax was last seen walking away from a mental health appointment, police said.

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“We are grieved to report that we have just received confirmation that our search for Linnea has ended in sorrow,” members of HelpFindLinnea.org said in a statement posted on its website. Arrangements for a Celebration of Life service are being made, the group said.

According to her parents, the teen suffered a breakdown while studying for finals.

Police say Lomax was last seen at 1 p.m. on June 26, leaving an outpatient therapy center off Howe Avenue in Sacramento. She was considered missing and at-risk due to her disappearance being "inconsistent with her normal behavior patterns," police said.

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She didn’t have her wallet or cell phone, Craig Lomax told NBC News in July. She had been prescribed medication for anxiety and depression, but she left her drugs behind, vanishing into California’s capital, he said.

Last month, a search party turned up a notebook belonging to Linnea Lomax near the American River bike trail. 

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Police carry one of the dozens of protesters arrested inside the state capitol in Sacramento, California, on Monday.

SACRAMENTO, Calif. -- A day of boisterous protests over cuts to higher education that included thousands of students swarming the state Capitol ended with dozens of arrests after demonstrators refused to leave the building.

Authorities on Monday evening arrested 68 people, most of whom will be charged with trespassing, the California Highway Patrol said. Four people were arrested earlier in the day.

Police started pulling out protesters who remained in the Capitol rotunda around 7:30 p.m. (10:30 p.m. ET), more than an hour after they began warning them with a bullhorn to leave. 

NBC Sacramento reported that some protesters identified themselves as being part of the Occupy Sacramento group.

Protesters chanted "We're doing this for your kids," as one by one they were lifted by the arms, handcuffed with plastic ties, and led away.

Students angry over steep tuition increases and fewer courses at California's public universities and colleges waved signs and chanted, "They say cut back; we say fight back."

Tuition has nearly doubled in the past five years, to $13,000 for resident undergraduates at University of California schools and to $6,400 at California State University schools. Community college fees are set to rise to $46 per unit by this summer, up from $20 per unit in 2007.

Democratic lawmakers addressed the group and lamented the deep cuts to higher education they have made in recent years.

"We were expecting to have a good future, but things are looking uncertain for a lot of families," said Alison Her, 19, a nursing student at California State University, Fresno. "I'm the oldest in my family, and I want my siblings to be able to go to college, too."

Public schools 'eroded year after year'
After the rally, hundreds of students lined up to enter the Capitol and filled conference rooms and hallways inside. Some met with lawmakers to lobby for increased funding for higher education, while others headed for the rotunda.

CHP officers allowed several hundred students to settle on the black and white marble floor of the rotunda before all four hallway entrances to the area were blocked. Another hundred students sat down in a hallway, communicating with fellow protesters by call and response, in a manner characteristic of the Occupy movement, The Daily Californian reported.

Several lawmakers watched from a second-floor balcony as the protesters were later arrested.

Outside the Capitol, hundreds of protesters who had lingered into the evening disbursed after the arrested protesters were taken away in vans. Officers in riot gear guarded the underground exits where they were taken out.

Earlier in the day, three women were arrested for disobeying an officer's order after trying to unfurl a banner on the second floor. A man was arrested outside the building for being in possession of a switchblade knife, the CHP said.

Gov. Jerry Brown said in a statement that the protest highlights the need for California voters to approve a tax increase he has proposed for the November ballot.

"The students today are reflecting the frustrations of millions of Californians who have seen their public schools and universities eroded year after year," said Brown, a Democrat. "That's why it's imperative that we get more tax revenue this November."

Brown's initiative would fund education and public safety programs by temporarily raising income taxes on people who make more than $250,000 a year and temporarily increasing the sales tax by half a cent.

The University of California Student Association has endorsed a rival initiative that would tax millionaires and earmark the revenue for education. The California Federation of Teachers and state PTA support that initiative.

Buses brought hundreds of students in for Monday's march from as far away as the University of California, Riverside, 450 miles south of Sacramento.

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The Associated Press contributed to this report.