A 13-year-old boy is to be tried as an adult after allegedly shooting dead his 9-year-old brother in a game of cops and robbers and the bother was not complying to the rules of the game in Pennsylvania.

The boy, Brayden Leroy Wright managed to get hold of his dad’s loaded handgun and shot dead his little brother during a row last Wednesday, say authorities in Pennsylvania, US.

According to the police in the are, the boy  allegedly admitted putting the gun’s barrel against the back of his brother’s head and pulling the trigger before putting it back where he found it.

The boys are said to have discovered the firearm in a sofa in their living room.

Wright is charged as an adult with criminal homicide and aggravated assault in the death of his brother, according to court documents.

The boys’ father, Mark Snyder, confirmed to police he keeps two loaded 9mm handguns in an unlocked compartment in the couch for home protection.

The teenager is scheduled to appear at a preliminary hearing at Franklin County Central Court on Monday.