An eight-year-old boy was briefly taken into custody after taking a gun into a Philadelphia school and allegedly threatening a classmate.
It is unclear where the boy got the gun, but police say they are holding the boy's uncle, on a charge of reckless endangerment.
City police detectives questioned the boy for several hours before releasing him.
"He said he's going to shoot me. He said he's going to make it a bloodbath and throw me in the dumpster," nine-year-old Fatimah Edwards told WCAU-TV.
She reported the threat to a teacher, who called police.
The boy took the 9mm gun to school in his book bag, said a police spokesman. "Ammunition was there, but the gun was unloaded."
No shots were fired.
The boy, whose name was not released, will not face criminal charges.
Under Pennsylvania law, children under 10 cannot be charged, said Cathie Abookire, a spokeswoman for the Philadelphia district attorney's office.
The boy's grandmother said: "My grandson needs to be punished. He needs to be talked to. But, then, he's a kid."