The parents of a seventh grade student suspected of opening fire at Sparks Middle School in Nevada may face charges if the gun he used came from home, police said.

A teacher was killed and two students were wounded in the shooting before the suspect turned the gun on himself.

Sparks Police Department Deputy Chief Tom Miller said investigators believe the 12-year-old brought the Ruger 9mm semi-automatic handgun from his home, but authorities have still not confirmed the gun's origins.

When asked by reporters if the parents could face charges for not keeping the gun away from the child, Miller said, "that is basically a question for the local prosecutor, but the potential is there."

More than half of US states, including Nevada, have a Child Access Prevention (CAP) law but the strength of the laws varies from state to state.

Nevada prohibits only intentional, knowing, or reckless provision of firearms to minors, which may nor may not apply in this case.

"It's a fairly straightforward civil liability case that a parent can be held liable for failing to adequately secure a gun away from a young person, and there have been a number of civil suits over the years, and a number of reported cases around the country of holding gun owners to the highest degree of care in securing their weapons," Jonathan Lowy, director of the Legal Action Project at the Brady Center to Prevent Gun Violence, told the Christian Science Monitor.

Police are still looking for a motive in the shooting that killed the popular teacher Michael Landsberry and wounded two other seventh graders.

Landsberry is being hailed as a hero for trying to stop the gunman and stalling him for precious seconds so other students could flee the area.

"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."

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