Police said the boy shot himself with a .38-caliber handgun about 6:55 p.m., The Philadelphia Inquirer reported.
He was taken to St. Christopher's Hospital for Children where he was in surgery, police said.
It wasn't known who, if anyone, was in the home with the boy when the shooting occurred, the newspaper said.
"All we can tell is, it was accidental," city police officer Chris Bennett said.
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