A 15-year-old girl who died after being stabbed with a kitchen knife, allegedly by her 14-year-old brother, at their family's home in Claremont was identified by authorities on Thursday.
Aspen Geurts was not breathing when officers discovered her shortly about 5 p.m. Wednesday after responding to a 911 call regarding a female stabbing victim in the 300 block of Andover Drive, according to the Claremont Police Department.
She was pronounced dead after attempts by Los Angeles County Fire Department emergency crews to resuscitate her were unsuccessful, a police official said.
The teens' parents were not home at the time of the stabbing, which began inside the home and ended in the backyard, Lt. Mike Ciszek said Thursday night.
The victim's 14-year-old brother was arrested on suspicion of murder after being questioned, according to Claremont police. They found the youngster walking away from the residence.
The brother's name has not been released.
The victim was stabbed with a kitchen knife, Ciszek told KTLA. The weapon was found on the brother when he was arrested, the lieutenant said.
At the siblings' school, Glendora High, students on Thursday were trying to process what had happened.
"A morbid mood at school today. Everybody's in shock," said one student. "It's horrible."
Another student said she had a class with the brother, saying he was "odd but pretty cool sometimes."
Others said they were utterly surprised by the teen's alleged actions.
Aspen Geurts was described as "very kind" and a lover of music and animals.
Video from the homicide scene on Wednesday evening showed investigators removing multiple brown paper evidence bags from the home, which still had Halloween decorations in front.
Geurts was identified as the victim by Ed Winter of the county coroner's office on Thursday. An autopsy has yet to be performed on the girl, who would have turned 16 next month, Winter said.
The homicide was the first in Claremont since 2009, Ciszek said.
"Stuff like that doesn't happen up here. This is a very ... conservative, quiet neighborhood," a neighbor said.
A teacher shared an email that was apparently sent to Claremont High School staff by the school's principal indicating that the victim was a 10th grader at Glendora High School. The brother was in the ninth grade at the same school, the email said.
A third sibling, a sister, was identified in the email as a 10th grader at Claremont High School.