OmG

An eight-year-old boy intentionally shot and killed his grandmother minutes after playing the violent video game Grand Theft Auto IV, US authorities said.

the child was able to access the family's gun and shoot the 90-year-old in the head while she was watching television.

The child told investigators that he accidentally shot the woman while playing with a firearm, WAFB-TV reported.

But evidence has led investigators to believe the child intentionally shot her in the back of the head as she watched TV, it added.

"So if you have a video game where someone shoots at a target, that's sort of practising shooting at a target.

"When you have a video game that is shooting at a human being, that is practising shooting at a human being."

The child is being looked after by his parents. The authorities are treating the shooting as a "homicide".

The boy cannot be charged with a crime because of his age, the sheriff's office said.