Officials have released the identity of a high school student killed after apparently shooting himself with a blank-firing prop pistol at St. George's Desert Hills High School.

St. George police Sgt. James Van Fleet says 15-year-old Tucker Thayer was killed. He says the incident is still under investigation.

Thayer, who was initially reported as being 17 years old but found to be 15, died of head injuries. The prop pistol was found in Thayer's hands shortly before the play "Oklahoma!" was scheduled to begin Saturday.

Thayer was the only person in the sound booth when the cast of "Oklahoma!" heard a loud noise at approximately 6:20 p.m.

Washington County School District Assistant Superintendent of Secondary Education Marshall Topham confirmed the boy's identity.

The district said in a statement that it was "troubled about the accessibility and use of an operable firearm on school property."

"The District will carefully consider our policies and procedures that apply in light of this tragic situation and take appropriate administrative action to insure the safety of our students and staff," the statement read.

The school gave permission to use the gun for the play because it was supposed to be in the possession of a parent at all times.

"At this time we do not know how the gun came into the possession of the student. It is still under investigation by the St. George Police Department and the Washington County School District," a district statement said.