The Ellis County Sheriff’s Office said a detention officer was killed on Monday. In a press release, officials said a detention officer was “murdered” by an inmate at approximately 3:45 p.m. The sheriff’s office held a press conference on Tuesday to provide updates about the death of 28-year-old Officer Isaiah Bias, who had been with the sheriff’s office for six years. “Most of the time, law enforcement officers and detention officers deal with good folks having a bad day. Occasionally, we deal with bad folks,” said Ellis County Sheriff Brad Norman. “I can honestly say that my staff, over the last day, has dealt with pure evil. May god bless Isaiah’s family, friends and colleagues.” Arron Semeion Thompson, who was in a single cell 23 hours a day, assaulted Officer Bais while he was moving him back into his cell. “It was a heinous, horrific, purposeful murder that was senseless and not needed,” Norman said. The sheriff could not go into further detail due to the ongoing investigation being handled by the Texas Rangers. Thompson, 45, was charged with capital murder for the officer’s death. Thomspon was arraigned and issued a bond of $2 million, according to a statement from the Ellis Co. Sheriff’s Office. Thompson had been in jail on three counts of assault on a public servant and an evading charge since November, officials said. He was transferred after the incident. Norman said he supported the death penalty, but it is up to the DA to decide if they will seek it. Check back and refresh this page for the latest update. As developments unfold, elements of this story may change.