As investigation continues into a shooting at a Nevada middle school Monday, the 12-year-old gunman's parents may now be facing charges if police can prove the gun used to kill a teacher and wound two students came from home.

"The potential is there [for charges to be filed]," Sparks Police Department Deputy Chief Tom Miller said.

Officials believe the seventh grader may have gotten the Ruger 9mm semi-automatic handgun he used in the attack from the residence he lived in with his family, according to ABC News. If verified, his parents could be prosecuted for going against Nevada law.

It is illegal in the state to knowingly let a child under the age of 18 have access to a firearm unless the child is accompanied by a parent, guardian or authorized adult.

A motive for the shooting has not been confirmed by authorities.

Police said the shooting began minutes before the first bell rang, calling all classes into session. The suspect took the gun out and shot a male student in the shoulder outside of the school before heading in the opposite direction, where he encountered math teacher Michael Landsberry, 45, who tried to get him to put the gun down before the student shot him in the chest.

The suspect then shot another male student in the abdomen before turning the gun on himself. The two injured students were brought to Renown Regional Medical Center and have since been upgraded to stable condition.

Police have not revealed the identity of the shooter out of respect for his family's privacy.

The middle school was not the only site of a shooting in Nevada on Monday. Benjamin Frazier, 41, killed one and injured two at Bally's Nightclub and Casino in Las Vegas following a dispute over a cover charge.