Weeks after the SWAT team was called to Hays County Jail to quell what a senior officer with the Sheriff’s Office called a “mini riot,” the investigation is continuing with no charges filed.

Lt. Dennis Gutierrez said inmates in late June set a fire and used mattresses to block windows and security cameras in one housing area commonly referred to as a “tank” that can house up to 24 individuals. “They started a mini-fire, and we are still trying to figure out how...