RICHMOND, Ind. — The mother of a 14-year-old who carried a pistol and rifle into Dennis Intermediate School Thursday morning called 911 to alert officials to the imminent danger at the school.

That call is being credited with saving lives Thursday. The Indiana State Police confirmed Friday afternoon in a news release that the mother placed the call that enabled the school to implement its lockdown procedures and law enforcement to begin responding to the school.

Coroner Ron Stevens identified the shooter Friday, but Pal Item is not reporting his name because of his age. Stevens also said he transported the shooter's body early Friday to the Montgomery County Coroner's Office in Dayton, Ohio, where an autopsy was completed Friday afternoon. The state police release said the shooter died from a single, self-inflicted gunshot wound.

The preliminary autopsy reports indicate the shooter did not sustain any other gunshot wounds or trauma. Final autopsy results will not be available for several weeks, according to the release.

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RCS Superintendent Todd Terrill said during a news conference Friday that the shooter was not a student; however, he wouldn’t say whether the shooter had ever attended Dennis or any other RCS school.

"At this time, I choose not to talk about him and his status with Richmond Community Schools other than to say that he was not a student at this time," Terrill said.

Wayne County Emergency Communications received a call after 8 a.m. Thursday about possible violence at Dennis, which is attended by students in grades 5 through 8. The school's lockdown protocol included locking exterior doors, classroom doors and stairwell doors.

A state police release earlier Friday emphasized that the advance notification that allowed the school to lock down and officers to respond "undoubtedly prevented injury to students and faculty." Richmond Police Department Chief Jim Branum also said at the scene that the locked doors and police response because of that call saved lives.

Two RPD officers arrived about the same time as the shooter, watching him shoot out the glass on a north door, labeled 13, and enter the school. Branum said the shooter carried a pistol and a rifle as he entered the school. The initial RPD officers on scene followed him into the building, where the shooter passed classrooms full of students who were safely behind locked doors.

Terrill said Friday that one armed school resource officer was on duty Thursday morning at Dennis. The district has three others assigned to other buildings, and those three rushed to the scene when the incident took place.

"(The impact) was undeniable," Terrill said of the resource officers. "The drills that they do, him knowing that building in such a way, the other resource officers having that familiarity with our building — more so than the responding police — it was crucial because then as they grouped up with different groups they were able to have that insight, understanding and knowledge of our building to move efficiently and effectively."

Branum said he was near the school when he heard one of his officers radio that shots had been fired. Branum joined with a group of officers from RPD, the sheriff's department and the state police to enter the building from the east side. They followed the sounds of gunshots and information relayed by dispatchers from someone at Dennis who used the school's video system to track the shooter's movements. They found him in the south stairwell.

Branum, who said the gunshots were likely the shooter trying to break through the door, said officers yelled from the first floor to the shooter, asking and urging him to surrender. He, however, exchanged gunfire with officers approaching from the second floor, then he shot and killed himself.

One officer, Richmond Police Department Chief Jim Branum said, reported being struck by splinters from the door when the shooter fired into it.

Students occupied classrooms on the second floor near the stairwell, Branum said.

"Students could definitely hear it, because I could hear it on the first floor," Branum said of the shooting. "They were pretty close."

After the building was searched room-by-room, the situation was declared safe. Students were escorted to buses on North West Seventh Street, where nervous parents had been gathering across the street to await word about their students.

"I'm scared for my little girl. I just want her with me. I'm waiting to get her with me," said Angie Bryant, the parent of a seventh-grader who drove to the scene after receiving a phone call about the active-shooter event. "I was scared. My stomach dropped to my feet."

Some, even after hearing their students were safe, remained to actually see their students load onto the buses.

"I'm way more relaxed now, but I want them to know I'm here for them," Mark Poe said about his twin, eighth-grade daughters Maci and Megan Poe. "It's been probably the most nerve-wracking day of school since they've been in school. It's very scary to think your children are in danger."

Parents and students were then reunited at Civic Hall Performing Arts Center at Richmond High School.

Investigators on Thursday executed a search warrant at a home in the 100 block of South West 16th Street. Branum said they also had a search warrant for a car.

Because RPD and Wayne County Sheriff's Office officers were involved in the gunfire, Branum said he and Sheriff Jeff Cappa decided the Indiana State Police should investigate the active-shooter event. State police investigators completed their on-site work Friday morning and turned the Dennis building back over to Richmond Community Schools. However, the investigation continues.

The state police said Friday that no additional information from the ongoing investigation would be released at this time. The investigation would reasonably "expect investigators have, or will be, speaking with anyone who has knowledge of the deceased, as well as interviewing school staff, students and neighbors," according to the state police.

The Pal Item on Friday morning emailed a list of questions to state police Sgt. John Bowling, who has only responded through the news releases. Once the investigation has been completed, the release said, the information will be forwarded to the Wayne County Prosecutor's Office for review.

Branum said that officers in Wayne County train on active-shooter scenarios in schools, something he said 30 years ago he never would have imagined necessary. Officers are trained to attack the situation and not wait for the SWAT team.

"Thank God we did train that way countywide," Branum said. "We did what was needed to do and got it accomplished. Lives were saved partly by what the school did and their protocols with locking doors, and locking the double door at the top of the stairs was huge."