The 19 firefighters killed in Arizona's Yarnell Hill Fire were among "the best of the best" in their field, say peers—but that wasn't enough to protect members of the Granite Mountain Interagency Hotshot Crew when the fire took a quick, unexpected turn. "Only Mother Nature might be able to explain" the details, says a local fire chief, but the Wall Street Journal reports that the men faced a "burn over," with flames shifting direction too quickly for the firefighters to avoid them. At the time, the men were between a pair of ridges, the Arizona Republic notes, and thunderstorms overhead combined with erratic winds and drought conditions for "explosive fire behavior," one official tells ABC News.
Up to 10 people selected from around the country will investigate the deaths and issue a report. Burn overs are among the biggest dangers for firefighters—including hotshots, who train at least 80 hours at the start of every fire season. There are some 110 such groups in the US, with about 20 members each, the Journal notes. But this team is the only one that's part of a city fire department. At 4:50pm on Sunday, the men radioed to say their fire shelters were set up, a forestry official says, per the Guardian; it was the crew's last transmission. Crews weren't able to access the area for hours. "It was too hot and smokey," says a forestry official.