A 9-year-old boy fatally shot his 13-year-old sister in Mississippi on Saturday afternoon when she refused to hand over a video game controller, authorities said.

The victim, Dijonae White, was shot in the back of the head and the bullet entered her brain, Monroe County Sheriff Cecil Cantrell told reporters, according to WLOV-TV.

White was a student at Tupelo Middle School, the station reported.

Cantrell, who said he had never seen a case like this one, confirmed late Sunday the girl died from her injuries after being rushed to Le Bonheur's Children's Hospital in Memphis, Tenn.

White's brother wanted a video game controller in her possession and grabbed a gun when she refused, police said. It remains unclear how the firearm used in the shooting had been accessed.

The children's mother was in another room feeding other children lunch at the time of the incident, authorities said.

The sheriff added that the circumstances of the shooting are still being investigated, and that he is unsure what consequences the boy will face at this time, WLOV-TV reported.

Monroe County is in northeast Mississippi.

The Associated Press contributed to this report.