Tragedy continues in the battle against the Arizona wildfire as 19 firefighters were killed while attempting to control the fire, resulting in what is reportedly the "deadliest incident for firefighters" since September 11, 2001.

Out of the 20-man crew, all but one were killed while trying to deploy fire shelters designed to trap in breathable air and deflect flames and heat, reports NBC News.

The deceased were all part of the Granite Mountain Hotshots, an elite group of firefighters from Prescott, Arizona.

"Every day they took on risks. They were alert to those risks, but in this case [there were] extreme burning conditions, some unusual wind and then we're waiting to see whatever else, what other factors may be involved," said Prescott National Forest spokeswoman Mary Rasmussen.

The only surviving member of the team was at a different location during the tragedy.

"If you ever met them, you would meet the finest, most dedicated people," said Prescott Fire Chief Dan Fraijo.

"These are the guys that will go out there with 40, 50 pounds of equipment. They'll sleep out there as they try to develop fire lines and put protection between homes and natural resources and still try to remain safe."

The Yarnell Hill Fire, which was believed to have started by lightning, had consumed roughly 2,000 acres and 200 buildings thus far.

According to LA Times, this is the worst firefight fatality since 1933, when 25 were lost to L.A.'s Griffith Park fire.

Out thoughts go out to the friends and families of the firefighters.