An eight-year-old, in Antrim, picked up a viable pipe bomb outside his school and brought it into his classroom to show his teacher.
The Northern Ireland Police Service was alerted and the British Army was brought in to diffuse the device.
St Comgall's Catholic Primary and St Jospeh's, a school about an hour from St Comgall's, in Antrim, was also targeted in a bomb alert. No devices were found at St Joseph's.
The eight-year-old, Brendan Shannon, was cycling to school with his twin sister, Ciara, when he found a "golden pipe thing" in the playground.
He said "It was like a golden pipe bomb because it had wire and rope hanging out of it."
“I just got off my bike and just touched it to see if it was okay or not. It was OK so I just lifted it up,” he said. “I gave it to a teacher and told her where it was.”
The school's 400 pupils and the teachers were evacuated to a nearby Church hall.
Brendan's father said "I was very worried and very scared when I heard that my son had gone out into the playground, saw something and lifted it up."
Hilary Cush, the school's principal, said "It’s absolutely crazy. It’s unbelievable that innocent children should be caught up in something like this…They don’t have to be subjected to this type of horror and nightmare.”
Chief Inspector Simon Walls, of the PSNI called the placement of the pipe bomb in a school "despicable". He said "You take your children to be educated, not to be put at risk by violent and mindless people who have absolutely nothing to say to Antrim or to wider society.”
David Ford, Northern Ireland's Minister for Justice, has said that there was local suspicion that the Real Ulster Freedom Fighters were responsible for the pipe bomb at St Comgalls.