Nevada School Shooter's Parents May Face Charges if Gun Came From Home The 12-year-old shooter likely got the gun from his residence, police say.

Oct. 22, 2013 -- The parents of a seventh grade student who killed a teacher and wounded two students before taking his own life could face charges if police determine the boy got the semi-automatic gun from home, police said today.

"The potential is there [for charges to be filed]," said Sparks Police Department Deputy Chief Tom Miller. He said that decision would have to be left up to the local prosecutor's office.

Miller said investigators believe the 12-year-old obtained the Ruger 9mm semi-automatic handgun from his home, however authorities are still trying to confirm the origin of the firearm.

He declined to identify the boy out of respect for his grieving family, but said he was a seventh grade student at Sparks Middle School.

One day after the shooting that took the life of a Marine veteran turned math teacher and left two students wounded, police said they were trying to determine what caused the student to snap.

Miller declined to address reports that the shooter may have been bullied, but Faith Ebans, a student who said she had math class with the gunman, told ABC News she believed he had been made fun of at school.

"I saw kids pushing him around and doing a lot of mean things to him," she said.

"I guess one day he got tripped and my friends said, 'Trip them back," she said. "But I guess he just decided just to shoot them."

It was not immediately known whether the gunman targeted his victims or shot indiscriminately, police said.

The shooting erupted on the first Monday back from fall break, minutes before the morning bell when police said the suspect took out his gun and shot a student outside near the north hallway of the school.

At that point, the shooter went south, where police said he encountered Michael Landsberry, 45, a math teacher at the school.

"Mr. Landsberry calmly walked toward the shooter, putting his hands up in a motion to try and stop the individual's actions," Washoe County School District Chief of Police Mike Mieras said.

Instead, he said the former Marine and member of the Nevada National Guard was shot in the chest.

The suspect shot another student in the abdomen, police said, before he took his own life with a self-inflicted gunshot.

The two wounded boys were taken to Renown Regional Medical Center and were later updated from critical to stable condition with non-life threatening injuries.

As the Sparks community grieves and school remains closed for the week, police said the carnage could have been even worse.

Miller said there was evidence the suspect tried to get into the school, however, he was unable to since the building was on lockdown.

Landsberry, who stopped the suspect and tried to shield students, was hailed as a dedicated teacher who was a hero all the way to the end.

"He truly is a hero," Washoe County School District Superintendent Pedro Martinez said. "He was a beloved teacher, beloved father. He will not be forgotten."

Landsberry started his teaching career in 2001 and had been at Sparks Middle School since 2006, according to administrators.

The math teacher, whose one classroom rule, according to his webpage, was "Thou shall not annoy Mr. L," took the time out of his schedule to coach boys basketball and girls volleyball at Sparks Middle School. He also coached girls soccer at Sparks High School, Mieras said.

Chanda Landsberry, the slain teacher's sister-in-law, told ABC News that he left behind a wife, Sharon, and two step-daughters.

Tributes poured in on social media for Landsberry from his current and former students.

"You were my biggest motivator, kept me on my feet, heard me out," a former student wrote. "Why you? Why do the good ones have to leave?"