An 11-year-old was told to clean his room. Instead he killed his grandmother and himself

Eleven-year-old boy kills grandmother and himself after refusing to clean his room. / ABC

An Arizona boy fatally shot his grandmother, then killed himself at the weekend, after being instructed to clean his room, his grandfather told authorities.

Doyle Herbert called police to report that his wife and their 11-year-old grandson were dead in an apparent murder-suicide, a spokesman for the Maricopa County Sheriff's Office, Joaquin Enriquez, said.

Hebert told authorities the boy shot his 65-year-old grandmother, Yvonne Woodward, in the back of the head after they'd asked him repeatedly throughout the day to pick up after himself.

The boy was apparently "being stubborn about it," according to the statement. After killing his grandmother, the boy turned the handgun - which belonged to his grandfather - on himself, the statement said.

The couple had just sat down in their living room in their Litchfield Park, Arizona, home, located about 30km west of Phoenix, to watch television when the boy approached his grandmother from behind and shot her, the statement said.

Herbert told police he initially chased after his grandson but stopped to perform first aid on his wife.

Neighbours told a CNN affiliate that the boy was known for playing around the neighbourhood and was part of a "nice family".

"It really hasn't set in just yet. I mean this is a nice neighbourhood, it's really quiet - as you can see - it's just a tragic, tragic thing," neighbour Walter Venerable told azfamily.

The boy's grandfather told detectives he and his wife had full custody of their grandson. Investigators have not found evidence that suggests the boy wanted to harm others or himself before this incident.

An 11-year-old boy in Arizona shot his grandmother in the back of the head as she watched television, then turned the gun on himself -- all because she had asked him to clean his room, deputies said. https://t.co/vqtW0BxgSY

— WSVN 7 News (@wsvn) November 5, 2018

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