One student died and another was arrested after a dangerous high school shooting in New Mexico on Aug. 12.

Albuquerque Police Department (APD) is trying to determine exactly how Bennie Hargrove was shot dead at Washington Middle School in downtown Albuquerque.

Investigators believe Hargrove was enjoying his lunch break when he saw school bully Juan Saucedo assault a classmate. The 13-year-old reportedly approached Saucedo and warned him not to bully or beat up the smaller boy.

However, the school bully suddenly drew a handgun from his waistband and shot Hargrove multiple times. A school resource officer heard the gunshots and initially thought they came from illegal fireworks. However, she quickly realized students were running and screaming, “He has a gun.”

The employee saw the accused standing over Hargrove’s body with the gun in possession. Hargrove was transported to the University of New Mexico Hospital emergency room, and pronounced dead.

APD officers arrested Saucedo and charged him with carrying a lethal weapon to school, and murder.

Albuquerque Public Schools expressed condolences to the adolescent’s grieving family members.

“I want to send out my thoughts and prayers to all of our students, all of our families that are impacted by this horrible event,” Superintendent Scott Elder said according to USA Today.

APD Chief of Police Harold Medina described Hargrove as a hero who sacrificed himself for a safer school yard.

“He stood up for a friend and tried to deescalate a violent confrontation between classmates,” Medina said according to the Associated Press. “[This is] a tragedy that has shaken our community.”

When asked about his son’s behavior, Saucedo’s father realized his gun was missing on the day of the attack. He thought his wife had taken it but she confirmed she did not. He only realized something was wrong when he drove by the school, and saw several patrol cars and fire trucks parked outside the building.

One witness who attends the same school revealed Saucedo used to be much better behaved. He only recently behaved as if he belonged to a gang after being bullied himself.

School officials confirmed classes have resumed, and students will be offered counseling and other support services. There will also be a heavier police presence to promote a stronger sense of security.

“There is a lot of pressure in the community, people are nervous,” Elder said according to the newswire agency. “It was a terrible incident that happened between two people … [and] this should not happen in the community–it certainly should not happen at a school.”