The suspect, who wasn't injured and was not identified, was taken into custody, police said.
Jason Seaman, 29, a former football player at Southern Illinois University and a 13-year-old female student were wounded by gunfire in the shooting, which broke out around 9 a.m. on Friday morning at a middle school in Noblesville, a town of 62,000 just northeast of Indianapolis.
While there are no fatalities due to the shooting, Mahomet-Seymour High School alumnus Jason Seaman (class of 2007) was among the shooting victims.
Noblesville West Middle School Principal Stacey Swan and superintendent Beth Niedermeyer are also slated to be in attendance. Her family says she's hospitalized in critical but stable condition.
That's when Seaman tackled the shooter and swatted the gun away from him, possibly saving others from getting injured.
President Trump has thanked Noblesville West Middle School teacher Jason Seaman for his heroic efforts Friday in his science classroom. "His quick and automatic action is begin talking about all over the word!"
Stonebraker told ABC News that Seaman threw a basketball at the shooter and ran toward the bullets as screaming students sought cover behind a table.
"It's just a shock he would do something like that", Stonebraker said.
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Noblesville High School senior Jackson Ramsey started a GoFundMe fundraising effort for Seaman.
A man many are praising as a hero for his actions during a school shooting in Noblesville will speak for the first time on Monday. "When the safety of the kids is at hand, it's not surprising to me that he was going to do what he had to do". An unnamed student said that Seaman tackled the shooter. "You'll be proud of them, too".
"My prayers are w/the Noblesville community, especially those who are injured & those who witnessed an active shooter situation- something no one should ever have to go through".
Higgins said her son was shaken up but knew little about what happened.
"Karen and I are praying for the victims of the awful shooting in IN", he said. "A lovely girl. I can only imagine why this happened". "You're the reason I teach". The school's academic year was scheduled to end next Friday.
No other details were immediately available.