Authorities in northern Illinois say a 15-year-old boy is in fair condition after his 12-year-old brother accidentally shot him in the abdomen with a .22-caliber rifle.

McHenry County Sheriff's Lt. James Popovits tells The (Crystal Lake) Northwest Herald that the two brothers were playing with the rifle on Tuesday at a house near the northern Illinois community of Harvard when the younger boy pulled the trigger. Authorities say the boys didn't realize the gun was loaded.

The 15-year-old boy was flown to Rockford Memorial Hospital where he underwent surgery.

The sheriff's office continues to investigate. No charges have been filed.

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