MESA, AZ - Authorities say three guns were found in the home of a Mesa high school student arrested Thursday for threats to kill herself and some of her peers.
According to Sgt. Brandon Jones with the Maricopa County Sheriff's Office, the 16-year-old girl is a student and teacher assistant at Red Mountain High School, near Brown and Power roads.
Sheriff Joe Arpaio said the girl had been asking her parents where the guns were kept in the house, so her father was "alarmed" and put trigger locks on each gun.
Jones said the girl posted threats three days ago on a YouTube channel owned by a transgender community in Toronto, Canada.
The owner of the channel contacted Toronto police, and they then tracked down the poster, Jones said.
Toronto police then contacted MCSO, which launched an investigation at 10:30 p.m. Wednesday.
Part of the post reportedly said the following: "I now literally have a plan of seriously hurting... killing... murdering people in my high school. And a playlist to do it."
According to Jones, the post went on to say, "I WORK at the high school as a student teacher basically... which is why no one can find out about me somewhat accidentally planning to blow up the school. (and yes... it would be super easy...)"
MCSO went to the home of the girl's parents where the girl admitted to making the post among other statements, Jones said.
Jones said detectives entered the home and found a semi-automatic .40 caliber, a .357 revolver, and a .22 revolver.
Detectives also seized two computers in the home to process more evidence, Jones said.
Arpaio said in a news conference that the girl planned to bomb the school and shoot others.
The girl told detectives she had been planning this before the Connecticut school tragedy last week, Arpaio said.
In interviews with detectives, the girl's parents said she has a history of mental health issues and has been seen by a psychiatrist, according to Jones.
The girl was taken to the Maricopa County Juvenile Detention and will be charged as a juvenile, Arpaio said.
The girl is facing charges of one count of computer tampering and one count of threatening and intimidating.