Arizona officials on Tuesday launched an investigation into the deadly wildfire that killed almost an entire crew of firefighters—while the fire remains completely uncontained. The 19 firefighters’ bodies were found by their safety shelters, leading investigators to believe they died while trapped in them. A forestry official said Monday that the firefighters lacked a proper escape route when the winds shifted course and flames overtook them. The identities of members of the crew, the Granite Mountain Hotshots, were released on Monday. The fire killed about a third of Prescott’s sworn firefighters. Meanwhile, the deadly Yarnell wildfire has already burned through 8,500 acres and continues unabated.