The school was on lockdown during the incident, but the lockdown has been lifted.
As of early Saturday, authorities had not identified the student or filed charges against him.
On Friday morning, officers also responded to another "communicated threat" at Noblesville High School, but Jowitt said police believed that's nothing beyond a threat.
The shooting, by CNN's count, was the 23rd in the United States this year and comes just a week after a high school student in Santa Fe, Texas, shot and killed eight classmates and two teachers.
The teen, she said, would be the last person she would imagine being shot in school. She described him as a student, and that he shot at someone in the room, and one student was injured.
There was some kind of intervention in the school, someone tackled or in some way stopped the shooter.
Other kids ran out of the building and into a nearby field where they called their parents and asked them to collect them. The suspect in that shooting, Dimitrios Pagourtzis, a 17-year-old student at the school, is also alleged to have placed rudimentary bombs in the area.
"She's a popular girl", said Jayden Williams, an eighth-grade student in show choir with her. The ages and conditions of the victims have not been released.
The teacher was taken to IU Health Methodist Hospital.
Noblesville Schools Superintendent Beth Niedermeyer said she had just visited with the families of the victims and asked that, while cards and kind wishes were welcome, people stay away from the hospital to allow the family to have some peace.
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In the video, an officer approached Brown after noticing his Mercedes sedan was parked across two disabled spots at the drugstore. An officer later is heard saying to another, "He was being an ass and trying to hide something ". "So what", the officer said.
Police said they arrested the shooter and said the "situation resolved fairly quickly", but did not confirm the accounts of Seaman's reaction or details about how they arrested the shooter.
"Please pray for my son Jason".
Arrangements for students returning to school in the coming days were still in process, Barnes and Niedermeyer said.
"But then when it happens you want it to somehow be prevented from happening again", he said.
"Our prayers are with him and his family".
"I especially remember that he would throw himself on top of the shooter if he had to", she said.
In an Instagram post Thursday, she talked about what a great day she'd had at school making a movie in choir class and playing laser tag.
After Friday's shooting, Carly Novel, a Marjory Stoneman student, tweeted: "Noblesville Middle School students I am so sorry".
Noblesville Police Department has confirmed that a teacher and child suffered gunshot wounds during an active shooter situation at West Middle School, near Morse Reservoir. Police are onsite at the high school.