BLACK ROCK CITY, Nev. -- Under unusually heavy security, Burning Man's tens of thousands of participants finished their annual ritual by burning an elaborate wooden temple a day after a man was burned to death in another fire.

More than 600 volunteers and staff ringed the perimeter of the Temple, backed up by a hastily installed metal security fence. The fence and additional security were new conditions sought by the federal land manager, said Burning Man co-founder Crimson Rose.

Authorities said Aaron Joel Mitchell, 41, died Sunday morning after he ran into the Burning Man structure fire Saturday night. Rose said federal Bureau of Land Management officials wanted Burning Man to call off the Temple burn, the ceremonial finish to the weeklong festival of 70,000 people in the Nevada desert. She said the government wanted 350 extra security guards. Burning Man found nearly double that number.

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"We are showing the government we can step forward," Rose said as she joined with other perimeter guards. "It is a testament to our spirit. We have a ritual to complete."

Authorities are still investigating Mitchell's death. Rose, who helped manage security for the fire in which Mitchell was burned, said it’s still not clear if he was running directly into the fire or was running toward it and then fell when perimeter guards tried to stop him. Mitchell was not drunk, authorities said, but toxicology tests are pending.

Rose said Burning Man staff are still struggling with what, if anything, they could have done to prevent the 41-year-old from running into the inferno.

“We ask that all the time,” she said. “Why would anybody do anything like that? He was determined. It’s bewildering. I just go ‘why?’”

Mitchell, 41, was at his first Burning Man, according to his mother, Johnnye Mitchell. She said her son grew up in McAlester, Okla., but was living in Switzerland with his wife.

"He's 41, but they are always your baby," Mitchell said of her son, who she and others called Joel. Mitchell has a younger brother.

"He was loving and a nice person," his mother said. "Joel liked hiking and outdoors, running."

His father, Donald Mitchell, said he was a good son.

“You just never want something like this to happen,” he said.

The couple said they saw their son on Aug. 1 before he headed to Oregon to go to a solar eclipse festival and then to Burning Man.

He worked in construction.

He was pronounced dead at 6:28 a.m. Sunday after being flown to the University of California-Davis burn center.

Burning Man officials are providing crisis counseling to witnesses and friends.

Photos of the incident show Mitchell racing toward the fire, dodging multiple safety rangers, and then plunging into the flames. Firefighters in fire-resistant gear pulled him out, rushed him to the on-site medical clinic, and then airlifted him to University of California-Davis Firefighters Burn Institute Regional Burn Center. He died at the burn center, authorities said. Officials have not yet released where Mitchell was camping during the festival.

The Pershing County Sheriff said Sunday night that the initial rescue efforts were hampered due to a portion of wooden Man effigy falling as rescuers attempted to pull Mitchell from the fire

“Rescuers had to leave him to allow the structure to fall and provide for rescuer safety before they could go back into the flames to extract Aaron from the debris,” the statement said.

Rangers who worked the event are told in advance to look out for three kinds of people likely to rush toward the fire: people trying to get attention, like streakers, people who are on drugs or intoxicated and don't understand the danger, and the suicidal.

Burning Man’s event takes place on BLM-managed land, and Rose said she was unwilling to let federal officials abrogate attendees’ First Amendment rights to peaceably assemble on public property. She said the organization has long pushed back against government officials skeptical that so many people can come together to create a community from scratch every year, treating each other with respect, tolerance and understanding. That so many people volunteered to stand guard is a testament to the Burning Man ethos, she said.

“It feels so good to be showing we can rally the community to create miracles,” she said. “That’s what gives me hope from the seething mass of humanity.”

The event formally ends Monday with Exodus, when tens of thousands of cars, trucks, buses and RVs flood out of the desert to make the two-hour drive back to Reno and points elsewhere.

Statement on Incident During Saturday Burn

Burning Man's Man goes up in flames