HILLIARD, OH (WCMH) – A Hilliard Davidson High School student is in custody after prosecutors said he was planning a school shooting.

According to Franklin County Prosecutor Ron O’Brien, another student came forward and told a school resource officer that 16-year-old sophomore John Staley III was plotting an attack. Then, on September 22nd Staley was suspended from school and was under surveillance by Franklin County Sheriff’s deputies. He was later arrested on the OSU campus area on Friday.

“This could have been a serious tragedy that we have seen, heard and read about in other parts of the country,” said O’Brien.

Police said Staley is being held in the Franklin County juvenile detention center. He was charged with conspiracy to commit murder after a joint investigation involving the Franklin County Sheriff’s Office, Hilliard Police, Hilliard schools and the FBI.

“He did in fact recruit other people as part of this plan to help carry it out,” said O’Brien

He said Staley had drawn up a detailed map, visited a gun store and asked four or five other students to help him carry out the attack.

“The diagram laying out the plan including listed weapons and the personnel, number of people needed to carry it out,” he said.

O’Brien said Staley planned to have 15 people help him, but he was stopped before any harm could be done.

“Today is certainly a day that we can be very thankful for a student that did the right thing and came forward,” said Hilliard Police Chief Robert Fisher.

Tonight, the school and community are safe.

“In today’s day in age no community is immune to threats of violence and violence in our schools,” said Hilliard City School superintendent Dr. John Marschhausen. “Only because a student had the courage to come forward and let our SRO (student resource officer) know with the HIlliard Police Department of something that bothered this student, we were we able to stop this plan before something terrible happened.”

O’Brien would not say if any other students would be arrested, but the investigation is on-going.

Dr. Marschhausen said other students connected to the plan have been removed from the school setting until it can be determined that there isn’t a threat in the school.

Abdi Abdi, a senior at Hilliard Davidson, told NBC4 he never thought this would happen at his school and described it as “crazy.”

“They were just trying to recruit more people, which sounds like to me, they were really trying to take basically a lot of students out,” Abdi said. “When you have that [many] people you’re trying to get into your group, then you’re trying to really cause really bad problems.”

Abdi said while it was nerve-racking to hear about the threat, he believes the district has the situation under control.

“I feel like I’m really safe and stuff, cause if I heard about this the first day it happened, then I would feel like I wouldn’t be safe,” Abdi said. “And I feel like the whole school probably would not go to school the next day or anything like that.”