A 14-year-old boy in Alabama has been charged with murder after confessing to killing five members of his own family, US police say.

The boy is accused of killing three siblings, aged six months, five and six, as well as his father John Sisk, 38, and stepmother Mary Sisk, 35.

He is being charged as a juvenile but could face being tried as an adult.

The shooting happened late on Monday in the small town of Elkmont in northern Alabama.

According to investigators, the boy initially called police to say he had heard gunfire coming from his family home and met officers outside the property.

He later confessed to the attack, the Limestone County Sheriff's Department said.

"Upon being confronted with some of the inconsistencies, he did admit to shooting the five family members. All five were family members and all five lived in the residence," spokesman Stephen Young said.

School officials there say they are providing mental health counsellors to students at the local school.

Gun violence is common in the US - according to one monitoring site there have been almost 300 mass shootings this year alone.

Seven people were killed at the weekend in a series of random shootings in Texas, with the suspect identified as a 36-year-old man recently fired from his job.

Last month, separate attacks in El Paso and Dayton left 31 people dead.

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