Friday’s school shooting involving two 15-year-old girls at Independence High School in Arizona has been declared a murder-suicide. Police say a suicide note has been found at the scene near the cafeteria.

"Information gathered by detectives reveal the two girls were very close friends, appeared to also be in a relationship," Glendale police spokeswoman Tracey Breeden said in a statement Friday afternoon.

Only two students involved in Arizona high school shooting

According to investigators, each girl was shot once and were pronounced dead at the scene.

A weapon was also discovered nearby.

Police believe the two girls were alone when the school shooting occurred and there are no other suspects in the case. It is believed one teen shot the other, then took her own life.

The teens have been identified, but police have not officially released their names due to their age. However, others who knew the girls have identified them as tenth graders Dorothy Dutiel and May Kieu.

Normal day at Independence High turned tragic

Friday morning at approximately 8 a.m., police responded to a call reporting a shooting at Independence High School in Glendale.

Police were on the scene within two minutes and the campus was put on lockdown.

The investigators found the dead girls in a covered patio area just outside the school’s cafeteria. Breeden said there were no additional threats made to the school, students, or staff.

One student was on her way to class when the gunfire erupted.

"Me and my friend were in front of the school and we heard like, two loud shots, and we thought it was just someone popping a bag or something," the student said. "We didn't know what it was, and then the bell rang and we went to class."

Glendale Mayor Jerry Weiers offered condolences to the families. He said Friday morning’s shooting was very personal to him as he lives close to Independence High and his daughter once attended there.

Shortly after the shooting, parents were immediately notified through emails, automatic phone calls and social media, said Brian Capistran, Superintendent of the Glendale Union High School District.

Many parents quickly arrived at the high school looking for their kids. Officials instructed parents to go to a nearby Walmart parking lot until students could be released. Sometime around 11:15 a.m., students began leaving the building and parents were picked up in groups via bus, then brought to the school.

Cell phone use by students during a lockdown is generally prohibited, but panicked parents flooded the district with phone calls and an exception was made to allow students to contact family.

School officials said classes will resume on Tuesday and social workers and counselors will be available to talk with students and staff.

No one yet can explain why Dorothy Dutiel and May Kieu would want to commit suicide, but police will continue the investigation of the events that led up to the Independence High School shooting in Arizona.