An out-of-control wildfire in central Arizona claimed the lives of 19 firefighters on Sunday, making it the single deadliest incident for firefighters since the September 11, 2001 attacks.

It was the third-most firefighters ever killed while battling a wildfire in the U.S., and the most since 1933, when 26 were killed fighting the Griffith Park blaze in Los Angeles, Calif.

All 19 firefighters were members of an elite crew called the Granite Mountain Hotshots.

"This is as dark a day as I can remember, with Arizona suffering the truly unimaginable loss of 19 wildland firefighters," Arizona Gov. Jan Brewer (R) said in a statement. "It may be days or longer before an investigation reveals how this tragedy occurred, but the essence we already know in our hearts: fighting fires is dangerous work. The risk is well-known to the brave men and women who don their gear and do battle against forest and flame."

The firefighters died while trying to control the Yarnell Hill Fire near the small town of Yarnell, Ariz., about 80 miles northwest of Phoenix. The fire destroyed more than 200 buildings in the town of approximately 700 residents. The town had already been evacuated.

The fire began Friday night from a lightning strike and grew over the weekend, rapidly spread to engulf over 2,000 acres.

Below, footage of the blaze from the Associated Press.