Police have arrested an 11-year-old boy after he was caught with a gun in an American school 'to protect himself' following last week's mass shooting tragedy in Newtown, Connecticut.

The boy allegedly said he feared another attack similar to the one that left 20 children dead at Sandy Hook Elementary School.

Students at the suburban West Kearns Elementary School in Salt Lake City told police the boy threatened them with the handgun by waving it at them. However, they didn't report the boy until several hours after the incident, so there was no 'lockdown'.

Instead, teachers and administrators confronted him and found he had an unloaded gun and ammunition in his backpack.

One student, Isabelle Rios, said the boy threatened her and other students. She said the boy pointed the gun to their heads and threatened to kill them if they told the teacher.

"I was scared out of my mind," she said.

The boy is now being held in juvenile detention on suspicion of possessing a dangerous weapon and aggravated assault.

The .22-calibre handgun had been left at the boy's home by a relative. Authorities have not released the child's name.

The child made statements to administrators and mentioned the shooting rampage last week in Newtown.

The boy told others that his parents sent him to school with the gun for protection, which his parents adamantly deny.

"The family is rocked by this. They have been very forthcoming," Granite School District spokesman Ben Horsley said.

"This kid made a mistake, and he knows it.

"He feels bad about it, and his parents are cooperating with the investigation. He will not be coming back to this school."


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