Deadly US fire rages after 19 killed Firefighters struggled to contain a runaway wildfire in the US state of Arizona Monday after 19 of their comrades were killed in one of the worst such incidents in US history and two towns were evacuated. The firefighters died while racing to contain the Yarnell Hill wildfire about 135 kilometres north of Phoenix, in what Arizona governor Jan Brewer called "as dark a day as I can remember." The Yarnell Hill fire, believed to have been ignited by lightning and fanned by high winds, broke out Friday and has swept across 2,000 acres, spreading rapidly through the dry, forested area. Officials said that the incident was under investigation but that the firefighters appeared to have deployed fire shelters - last-ditch protection equipment - just before they were engulfed in flames. "It's not reality for us, it hasn't really set in," Wade Ward, a visibly shocked Prescott Fire Department spokesman, told CNN early Monday. It's a very elite group of people who are highly trained, highly motivated, very fit... We don't know what happened. Hundreds of residents of Yarnell and Peeples Valley were meanwhile evacuated, officials said on a fire alert website, as the blaze continued to tear through the area. Record and near-record temperatures left much of the US southwest sweltering over the weekend, with Death Valley in California equalling the hottest ever June temperature in the United States, at 53 Celsius. As of Monday, there were over 40 active blazes in the four states, according to the inciweb fire information website.