They were an elite crew, among the most fearless firefighters around, so on Sunday when a wildfire threatened lives and property in nearby Yarnell, the Granite Mountain Hotshots rushed into the flames.

On Monday, a city sick with grief mourned them as heroes. Out of a crew of 20, only one survived after the blaze exploded as they tried to protect a stand of houses. Their bodies, some of them still inside protective tents, were collected and driven a hundred miles to Phoenix for autopsies in a somber procession of vans.

At midday, Prescott officials released the names of the victims, ranging in age from 21 to 43, including Billy Warneke, 25, whose wife is pregnant; Kevin Woyjeck, 21, who followed in his father’s footsteps to become a firefighter; and Andrew Ashcraft, 29, whose wife, Juliann, learned that he was dead while watching television with their children.

Prescott was in shock. Some of the firefighters’ vehicles remained parked near the fire station. Residents came and went all day, leaving tiny stuffed dogs, water bottles and American flags in groups of 19, along with the word “heroes” in large block letters, on a hastily assembled memorial along a fence.

Later Monday, more than 1,000 people gathered in the gymnasium of Embry-Riddle Aeronautical University to remember the firefighters. Some wept as the names and ages of the dead were flashed on a screen. There was a standing ovation for the firefighters in attendance.

All the while, the 8,000-acre fire continued to burn 30 miles away in Yarnell. City fire officials said the blaze that caused the deadliest firefighting disaster in Arizona’s history was “zero percent contained.”

Each family of a victim is being assisted by a liaison “not only in their grief, but also in the process of moving on,” said Wade Ward, a fire department spokesman. Meanwhile, a task force of investigators arrived to determine what happened, hoping to release preliminary results in three days. A formal memorial service is expected Wednesday.

“Prescott is sad today, sir,” said Bonnie Winters, who works with the mother of one of the dead firefighters. “It’s really hard,” she said, her eyes filling with tears. “I was out and about today, and besides the weather being so gray, so are people’s hearts.”

President Obama said in a statement that the firefighters were “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.”

Gov. Jan Brewer’s voice cracked several times as she praised the men at a news conference. “I said last night that my heart is breaking,” she said, adding, “I can’t imagine how the families who knew these individuals feel.”

Fire Chief Dan Fraijo expressed disbelief that 20 percent of his firefighters were gone, a loss that touched nearly every resident in a city of about 40,000. Grief counselors were dispatched to console and pray with any relative who requested it.

“This is a big number,” Stephen J. Pyne, a professor in the School of Life Sciences at Arizona State University and a well-known fire historian, said of the 19 deaths. “This is a new, sad standard.”

The shelter provides breathable air and some heat and fire protection.;

The last time so many firefighters perished in a single wildland fire was in 1933, when more than two dozen men died in Griffith Park in Los Angeles. The fire broke out as thousands of laborers were clearing trails and fixing roads as part of a Depression-era jobs program.

“You could tell the progress of the fire by the screams,” one witness said of that fire, according to an account posted on the Conference of California Historical Societies Web site. “The flames would catch a man and his screams would reach an awful pitch.”

John Marsh said Monday that one of the victims of the Yarnell fire was his son, Eric, 43. The younger Marsh was a nature lover, hunter, fisherman and rock climber who helped organize the crew years ago and loved his men, his father said.

The elder Marsh heard on television that a crew was missing and slumped when he eventually learned the crew’s name. His knew his son, married in 2011, was gone. “It wasn’t a good way to hear it,” he said.

Wendy Tollefsen said she worked out with many of the firefighters at Mile High Fitness. They were in excellent shape, trained to endure the physically and mentally draining job of fighting wildfires.

Fraijo said he did not know what contributed to the factors that trapped the firefighters, who were discovered with their emergency tents — designed to help fend off smoke and fire — deployed. Some of the dead were inside the tents and some were outside. A 20th member of the unit escaped because he was driving the crew’s truck, according to some reports.

This year’s Arizona fire season is “one of our worst ever,” said Trudy Thompson Rice, a spokeswoman for the Grand Canyon chapter of the Red Cross. “We’ve had a tremendous drought. We’re in a very dry cycle, with high winds. And it’s very, very hot.”

Rice spent Monday afternoon in a high school gym that the Red Cross had converted into a shelter in Wickenburg, one of two shelters opened to accommodate people affected by the Yarnell wildfire. The other shelter is in Prescott.

Fifty-five people stayed overnight in the two shelters, where therapy dogs comforted visitors and nurses examined people who had inhaled too much smoke or left medications behind when they fled.

But even those whose houses stood in the path of the flames and might soon be homeless were more shaken by the loss of the firefighters. “That’s what everyone is focused on right now,” Rice said. “They knew all these young firefighters. They taught them. They coached them in sports.”

At least 200 firefighters also battled the blaze Sunday, and more were on their way. Hundreds of homes were threatened, roads were closed and residents were given orders to evacuate, but could voluntarily remain with their homes if they wanted, Fraijo said.

The elite hotshot firefighting units are each made up of 20 people who study the science of wildfires and train hard to fight them. “The nature of our work requires us to endure physical hardships beyond most people’s experiences,” a Web site said.

The crews, whose name refers to being near the hottest part of a fire, began in Southern California in the late 1940s. Over time, they earned a reputation as being among the most fearless firefighters.

All the crews have a home base — the Granite Mountain Hotshots team is part of the Prescott Fire Department — and often are dispatched throughout the United States, Canada and Mexico to fight wildfires.

They face environmental extremes, long hours, bad food, and steep and rugged terrain. Running, hiking, core-abdomen training and yoga are included in the exercise regimen.

In April 2012, the Cronkite News Service described a Granite Mountain Hotshots training exercise in which members deployed the shelters.

A squad leader, Phillip “Mando” Maldonado, yelled, “Fire everywhere!” and the men hit the ground and formed a tight circle, “feet toward the approaching flames.”

Maldonado instructed them to hold down the edges of the shelter to keep out fire, smoke and heat, the report said. They were told to hug the ground hard, so they could breathe cooler air that would have less of an impact on their lungs.

According to the report, the crew had eight full-time members. Others worked from April until the end of the fire season in September.

“I knew these folks,” Fraijo said. He called them excellent, dedicated employees who stayed in shape.

The chief said he had no way of knowing why some of his hotshot team, which started in 2002 and included veterans of numerous wildfires in the West, did not survive.

“Typically they have a safety zone,” he said. “For whatever reason, they might not have made it [there]. I don’t know.”

Condolences came from officials across the nation. “Every day, thousands of brave Americans step up to protect people and property from the devastation of wildfire,” Agriculture Department Secretary Tom Vilsack said in a statement.

“They put their own lives on the line to do so,” he said.

Fears reported from Washington. Brady Dennis, Meeri Kim and Ruth Tam contributed to this report.