At a 3 p.m. news conference, Randy Taylor, assistant superintendent of the Metropolitan School District of Martinsville, said the shooting suspect was "no longer a student and shouldn't have been on school property."

Earlier reports indicated the teen had been expelled from the school.

Chance Jackson, 15, was shot twice in the stomach just after 7 a.m. near the doors on the west side of the school building.

"Our thoughts and prayers go out to the victim and his family," Taylor said. "We are very troubled by the senseless act of violence at our school."

Jackson's family released a statement, asking the public to pray for the boy, who underwent surgery and was in serious condition at Methodist Hospital.

"Chance Jackson is out of surgery and is currently in stable condition," the statement read. "We appreciate all of the thoughts, prayers and support and ask that you also pray for the families of all involved. Please respect our privacy as we focus on Chance's recovery."

The school system said it handled the situation properly.

"We had a plan in place, and we carried out that plan, keeping the well-being of students our top priority," Taylor said, adding that security will be increased at the school.

Robert Cline, Morgan County chief deputy prosecutor, said an exhaustive investigation was launched.

"All known witnesses were interviewed," Cline said. "As much evidence as possible was preserved and processed at the scene, and schools were secured almost immediately."

Indiana State Police Sgt. Curt Durnil said numerous agencies are involved in the investigation, taking a "coordinated teamwork approach."

The boy who was arrested posted a chilling message on Facebook earlier in the morning.

"Today is the day," the teen posted on his Facebook wall.

6News has been told the identity of the boy but isn't releasing it because he is a juvenile.

Durnil said investigators are poring through surveillance video and social media in search of "anything we can find out as to why, what type of motive, if it was a random thing."

Police found the gun they believe was used in the shooting.

This is an intentionally blurred picture of the teen who police say shot a student at a Martinsville school. The teen is a juvenile and hasn't been charged as an adult, so 6News is not releasing his identity.

Martinsville Police Chief Jon Davis said the school had no prior warning that a shooting might happen there.

Police said the shooting suspect left the school on foot and was walking along a nearby road when he was apprehended.

Jamin Shue said he knows the teen who was arrested and that there was no inkling of trouble.

"I've never seen him get in this much trouble before," Shue said. "He's just your average teenager. He has fun with his friends. He'll hang out around town."

The school was immediately locked down afterward, as were other schools in the district.

School officials instructed Martinsville West parents to wait at the maintenance building on South Ohio Street. Students were released early Friday afternoon. Classes were canceled for the day.

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