Four Las Vegas teenagers accused in the fatal beating of their high school classmate have agreed to plead guilty to voluntary manslaughter in a deal that will keep them from being tried as adults, lawyers said Thursday. The teens originally were charged in January as adults with second-degree murder and conspiracy in the November death of 17-year-old Jonathan Lewis Jr. Cellphone video of the fatal beating was shared across social media. The deal announced during a hearing Thursday before Clark County District Judge Tierra Jones calls for the four to be sent to juvenile court and face an undetermined length of imprisonment in a juvenile detention center.