FAIRVIEW TWP — A 15-year-old boy was taken into custody after a bomb threat was discovered Tuesday morning at Karns City High School.

The student is accused of writing the threat on a bathroom wall, state police said.

School police quickly determined “there was no viable threat” and there was no evacuation, said Cpl. Michael Lewis.

The threat also did not impact the district's dismissal time.

Security camera footage helped police in the investigation, Lewis said, and the boy later admitted writing the threat.

Authorities would not say what was written on the wall.

School police detained the teenager before state police were notified. The district has five school police officers, all of whom are retired state troopers.

The boy's parents were also notified and showed up at the school and later at the police barracks in Butler Township where troopers took him.

Lewis said he would be charged in Butler County juvenile court with a felony count of terroristic threats.

In a letter to parents, which was posted on the district's website Tuesday, Superintendent Eric Ritzert said that the district was “able to quickly identify the individual responsible for the threat and determined that no bomb existed.”

“The school day will continue as scheduled and school will be dismissed at the regular time,” Ritzert's message reads, in part.

He also urged people to speak up if they see or hear disturbing statements, and pledged to take “all appropriate disciplinary action under our student code of conduct and the Pennsylvania State law.”

This is the second time in less than a month that a student in the district has been arrested and charged after a bomb threat at the high school. In late February 18-year-old Garrett M. DeBacco of Cowansville was charged with felony threats to use weapons of mass destruction, after an incident on Feb. 20 in which he allegedly announced that he had found a bomb threat on the wall of a boys' bathroom.

That touched off an evacuation and a state police response, and DeBacco was ultimately charged after he allegedly admitted to writing the threat himself.