Sturbridge police released details on the April 19 attack on Thursday, June 8, after a news report linked to the footage of the beating.
According to investigators, the two 13-year-olds agreed to meet in the woods near Old Sturbridge Village and fight to settle an argument. However, during the fight, one of the boy's 17-year-old brother jumped into the scuffle. After they had finished beating the boy, they threatened to attack him with a machete next time.
Sturbridge Police Chief Earl Dessert called the attack an "unconscionable act" in a Facebook post. He did not say if the boy was injured.
The beaten boy called his stepfather about the fight, and the man confronted the teens at the corner of Arnold Road and Main Street around 5 p.m. The boys attacked him following an argument.
Police arrested the two teenagers shortly after the man called 911 a few minutes after the second fight.
Officials did not release the boys' names because of their age. They face 17 charges between the two of them, including nine felonies.
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