A Texas man being held in jail fatally assaulted a detention officer who was returning him to his cell following the one hour he was allowed out of his lockup each day, a sheriff said Tuesday. Isaiah Patrick Bias, a 28-year-old who worked at the Ellis County Sheriff's Office for over six years, was assaulted Monday afternoon at the county jail in Waxahachie, south of Dallas. Sheriff Brad Norman said during a Tuesday news conference that Arron Semeion Thompson, 45, from nearby Ennis, has been charged with capital murder in Bias' death.