LOS ANGELES: Police in Arizona said they arrested Thursday a 16 year-old female student who threatened in an online video to “kill everyone” at her high school then kill herself.

The young woman was a student of Red Mountain High School, in Mesa, a suburb of Phoenix, the office of Maricopa County Sheriff Joe Arpaio said in a statement.

“The threat was posted on a Youtube channel owned by a transgender community in Toronto, Canada,” the statement read.

The channel owner contacted Toronto police, who tracked the person that posted the video to the suburbs of Phoenix. Canadian police then contacted the sheriff's office late Wednesday, and within three hours they were able to find the suspect's home in Mesa.

Detectives went to the home, questioned the teen in the presence of her parents and then arrested her “after she admitted to posting the threat.”

The Youtube post alludes to the Sandy Hook Elementary School massacre, but said that she had planned her attack “well in advance” of the shooting there.

“I now literally have a plan of seriously hurting ... killing ... murdering people in my high school,” reads the part of the post.

It continues: “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...).”

The teen told detectives that “she was scared because she thinks she may really carry out the plans detailed in the post, and 'f@#king kill everyone'”, the statement read.

She also admitted that she had planned to “cut the wires to the security carts” on campus to slow down a police response.

The teen's parents said that their daughter had been seen by psychiatrist “and had recently been inquiring about where the guns were being kept in the house. The father said he was alarmed by his daughter's comments and took the additional safety precautions of placing trigger locks on each gun and safeguarding them in a gun safe.”

The father owns three handguns. Police let the father keep the weapons.

“We were very fortunate on this occasion to prevent another possible mass tragedy,” Arpaio said. “It takes more than just law enforcement though. We need the active cooperation of parents, members of the community, and friends and neighbors to effectively stop these potential disasters before they happen.”

The teen faces charges of one count of computer tampering and one count of threatening and intimidating, the statement read.