HAYWARD (KCBS / BCN) – A teenager found hanging from a tree branch in the Hayward Hills died of asphyxiation, although it’s unclear whether his death is a suicide or a homicide, authorities said Friday.

Police found the 15-year-old boy’s body Wednesday in a ravine behind a home in the 2100 block of Beckham Way, the day after a standoff with his twin brother who had apparently broken into the house wielding two knives.

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The boys’ names have not been released both because of their ages and because police have yet to determine any possible criminal charges. Both were students at Hayward High School who had never had any prior run-ins with police.

The surviving twin remains in the hospital recovering from self-inflicted stab wounds. Deputies with the Alameda County Sheriff’s Office used a stun gun on the boy, who asked the officers to shoot him.

“There’s no question the Taser saved this young man’s life on that day,” said Sgt. J.D. Nelson, a spokesman for the department.

“Had there not been a Taser, they would have been forced to use their firearms and that would have been more tragic than this already is.”

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Investigators are trying to determine whether the surviving boy played any role in his twin brother’s death.

Nelson said a note written by one of the boys offered investigators few clues.

“It does express unhappiness, although there’s no real reason why,” he said. “There’s nothing specifically pointed out. There’s no traumatic incident that’s pointed out.”

Nelson said investigators have not been able to talk at length to the boy because he is still recovering, and they are reluctant to question the parents extensively so soon after the death of their other son.

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