CLIFTON, N.J. -- Five 5th graders were arrested after police say they were planning to "cause damage" to Clifton High School during assembly Wednesday.
They have since been released into the custody of their parents.
The students, ages 10-11, were caught by teachers at School 11 who found their written plan about the alleged attack.
Clifton Police spokesman Robert Bracken says the students built a device -- but the device had no explosive properties.
"It wasn't a prank," Bracken said.
Police say they believe they had outside help and got their ideas from other events.
The students involved included boys and at least one girl, police say. All were sent home around 9:30 a.m.