Tragic loss ... May Kieu, 15, was found dead near the cafeteria of Independence High School in Glendale. Picture: Instagram

The bodies of Dorothy “Dot” Dutiel and May Kieu, who were in a relationship, were found near the cafeteria of Independence High School in Glendale on Friday.

Police said the girls were each shot once, and were declared dead at the scene. A weapon and suicide note were found near the bodies.

Glendale police spokesman Sergeant David Vidaure said one of the girls had obtained the weapon from her classmate, a 15-year-old boy, on the eve of the shooting after telling him “she needed it for protection”.

The classmate obliged by providing the girl with “a family-owned handgun, from his home, without the permission or knowledge of his parents,” Vidaure said.

Tragic ... the bodies of May Kieu and Dorothy Dutiel were found near the cafeteria area of Independence High School in Arizona. Picture: InstagramSource:Supplied

The male student has been co-operating with detectives, though his involvement will be reviewed by the Maricopa County Attorney’s Office for possible charges, Vidaure said.

Although police have not revealed who the shooter was, Dutiel is known to have left an eerie farewell tweet hours before the shooting. It read simply: “Good bye (:”

Her aunt Julie Moore said Dutiel’s mother was coming to terms with the horrific shooting.

“She’s got double heartache. She’s hurting very, very badly for the loss of her own child, but also somebody else’s child,” Moore told ABC 15.

“Dot was not an evil child by any means, I think she was a hurting child and for whatever reason she was in pain and felt this was the answer.”

May Kieu was named as one of the victims in the Arizona school shooting. Picture: InstagramSource:Supplied

Alleged shooter Dorothy Dutiel left a chilling goodbye on Twitter. Picture: InstagramSource:Supplied

Neither the two girls nor their classmate have been officially identified because all three are minors. However Dutiel was named by local media, while Kieu was identified by her sister, a teacher at the school.

Although the precise circumstances remain under investigation, evidence from the scene has led homicide detectives to determine one of the girls killed the other before taking her own life, and that no other students witnessed the shooting.

Their bodies, a suicide note and the pistol were found in a canopied patio area near the school cafeteria after gunfire erupted shortly after classes started, triggering a security lockdown of the campus as police initially searched the school grounds for suspects.

No surveillance video of the incident was captured, police said.

Anxious wait ... parents wait to reunite with their children outside Independence High School. Picture: Matt York/AP PhotoSource:AP

Mourning ... counsellors have been brought in to help students at Independence High School after two 15-year-old girls died in an apparent murder-suicide. Picture: AP Photo/Matt YorkSource:AP

On Tuesday, counsellors and social workers were brought to the 2000-student high school to help those returning to class for the first time since the incident.

In a Facebook message to parents and guardians, school principal Rob Ambrose offered condolences to the families of the two girls and acknowledged the outpouring of community support.

Suicide is the third-leading cause of death among American youths aged 10 to 24, resulting in 4600 lives lost each year, and firearms are the most common method for taking one’s own life, according to the US Centres for Disease Control and Prevention.

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