By OLGA R. RODRIGUEZ and DON THOMPSON

SACRAMENTO, Calif. (AP) — Three children that a relative called "beautiful great-grandbabies" were killed inside a California apartment by their father following a domestic violence altercation with his wife, authorities said Thursday.
California Highway Patrol officers arrested Robert Hodges, 33, on Interstate 80 in neighboring Sacramento at around midnight Thursday, said West Sacramento police Sgt. Roger Kinney.
The children were killed at the family's West Sacramento apartment after 9 p.m. PDT Wednesday. Police and first responders tried life-saving measures on the children, but all three were pronounced dead at the scene. Police have not revealed how the children were killed.
West Sacramento Police Sgt. Roger Kinney said the mother was a victim of domestic violence but that he didn't know the extent of her injuries.
He said she did not witness Hodges kill the children as it was initially reported. Sacramento television station KCRA earlier reported that Kinney told the station the woman had witnessed the killings.
Kinney said investigators told him "she was in close proximity."
The children's great-grandmother said relatives were unaware of any previous marital disputes.
The couple had been married more than a dozen years and had an 11-year-old boy, a 9-year-old girl and another boy, born in January, said Irene Aiello of West Sacramento.
"We don't understand what happened, we really don't," she told The Associated Press. "Everything appeared to be OK" between the couple.
She said the grandparents have yet to speak to Hodges or his wife. The children's names, ages and genders have not been released by authorities.
"Obviously, she's traumatized, and it's going to take some time to find out what's going on," Kinney said of the mother.
Neighbors called 911 to report a domestic violence incident, and as police were on the way to the apartment, someone called again to report the children were possibly dead, he said.
Kinney said a chaplain will be sent out to help neighbors of the victims and grief counselors will be made available to the officers who responded to the scene, as well as the Washington Unified School District, Kinney said.
"The officers are absolutely impacted, along with the firefighters, and certainly the family, the neighbors," he said. "It's horrific and it's very difficult to deal with."
A message left at a telephone number linked to Hodges' parents was not immediately returned.
"They were beautiful great-grandbabies," Aiello said.