An 11-year-old boy shot and killed his 65-year-old grandmother before killing himself in a disturbing murder-suicide over the weekend, that has shocked the Litchfield, Arizona community.

According to the local police, the boy – who lives with his grandparents Doyle and Yvonne Herbert who have full custody – refused to clean his room and was “stubborn” when his grandparents repeatedly asked him to do the chore.

At about 5pm, when the elderly couple were watching television, their young grandson snuck up behind them and shot his grandmother in the back of her head with his grandfather’s gun.

Stunned, grandfather Doyle started running after the boy but stopped and ran back to help his wife. Seconds later, he heard a second gunshot. When Doyle turned around, he saw the boy take a few steps back before falling to the ground, having shot himself.

The local Sheriff’s Department noted that there were no signs that the boy would harm himself or anyone else prior to the shocking murder-suicide, as it said in a statement: “In the preliminary stages of this investigation there had been no previous signs that the grandson might harm someone or himself and there was no cause for concern prior to this event.”

Investigations are ongoing.