An Oklahoma teenager has been sentenced to life in prison for killing his parents and three siblings.

Michael Bever was 16 when he and his older brother, Robert, stabbed their mother, father, two younger brothers and five-year-old sister to death in 2015.

Two sisters survived the attack, which was described as the worst single criminal event in the history of Broken Arrow city in Oklahoma.

Now 19, Michael Bever was convicted in May of five counts of first degree murder for his role in the killings.

The teenager's lawyers argued that he had been led astray by his older brother, who pleaded guilty to the killings in 2016 and was sentenced to life without parole.


While prosecutors urged that the horrific nature of his crime merited a sentence without parole, the jury recommended Michael Bever was granted life with parole.

Image: Robert Bever, pictured in 2015

Officers were alerted to the 2015 killing spree by an "open 911" call, in which the caller did not speak.

On arrival they were unable to get in through the front door of the house, but heard moaning and found the boys' injured sister before dragging her outside over fears the killer might still be inside.

Commenting at the time, neighbour Patricia Statham said: "It certainly is shocking. I'm shocked. I feel so bad for everyone who walks into that house.

"You can see it in the faces of the officers when they come out."

During Bever's sentencing a lawyer read a letter from the adoptive mother of the injured sister and the two-year-old who escaped unharmed, describing how the girls would spend their lives "looking over their shoulders".

The older sister, who still bears scars from the attack, "is terrified of that thought that her brother could possibly be paroled and what he might do to her," the letter said.