Updated

The 19 elite firefighters who died Sunday trying to put out a fast-moving wildfire in Arizona were the equivalent of firefighting special forces, highly trained to work in the most extreme environmental conditions.

Members of the Prescott Fire Department, they were also part of an interagency “hotshot” crew called the Granite Mountain Hotshots, formed in 2002. Each had undergone rigorous physical conditioning and specialized training in problem solving, safety and fire suppression.

Members are required to undergo an annual 80 hours of critical training and able to run 1.5 miles in just over 10 minutes. Even before that, they must pass the Arduous Work Capacity Test, which includes carrying a 45-pound pack on a 3-mile hike in 45 minutes.

“We are routinely exposed to extreme environmental conditions, long work hours, long travel hours and the most demanding of fireline tasks,” states the Granite Mountain Hotshots’ website.  “Comforts such as beds, showers and hot meals are not always common.”

According to the U.S. Forest Service, Hotshot crews started in Southern California in the late 1940s on the Cleveland and Angeles National Forests. They developed their name from a reference to being in the hottest part of the fire. Along with fighting wildfires, these crews also participate in search and rescue and disaster response assistance. All crews require their members to be available 24-hours per day, seven days a week during the fire season, which usually lasts about six months.

There are 112 Interagency Hotshot crews in existence today, stationed throughout the country. They can be employed by the US Forest Service, Bureau of Land Management, National Park Service, a state, city or county.  The Granite Mountain IHC is employed by the city of Prescott, Ariz.

“They were heroes — highly-skilled professionals who, like so many across our country do every day, selflessly put themselves in harm’s way to protect the lives and property of fellow citizens they would never meet,” President Obama said in a statement on Monday morning.

“Michelle and I join all Americans in sending our thoughts and prayers to the families of these brave firefighters and all whose lives have been upended by this terrible tragedy,” he added.

A Facebook page has been set up in remembrance of the firefighters, already amassing more than 190,000 “likes.”