A sweat lodge in central Arizona where two people were overcome and later died lacked the necessary building permit, an official said Monday.

Yavapai County building safety manager Jack Judd said there was no record of an application or permit for a temporary structure at the Angel Valley Retreat Center near Sedona.

At any one time, 55 to 65 people attending the "Spiritual Warrior" program hosted by self-help expert and author James Arthur Ray were crowded into the 415-square-foot space during a two-hour period Thursday night, Yavapai County sheriff's officials said.

Kirby Brown, 38, of Westtown, N.Y., and James Shore, 40, of Milwaukee died after being overcome in the sauna-like hut, which was built specifically for the five-day retreat. Nineteen other people were hospitalized with symptoms ranging from dehydration to kidney failure. One remained in critical condition Monday, and two others were in fair condition.

Sheriff's spokesman Dwight D'Evelyn said authorities believe Ray's staff either participated in erecting the structure or oversaw the construction. Ray's spokesman, Howard Bragman, declined to comment on the permit but said the resort's staff was under contract to build a sweat lodge to accommodate up to 75 people.

Resort owner Michael Hamilton declined to address the permit issue late Monday. His wife, Amayra Hamilton, said Saturday the sweat lodge, which was built with a wood frame and covered with layers of tarps and blankets, had been taken down.

Judd said no inspection of the structure was conducted before it was dismantled.

Verde Valley Fire Chief Jerry Doerksen, whose department responded to the initial 911 call of two people not breathing, said his department regularly inspects the Hamiltons' property. He said the couple never hesitates to ask questions, raise concerns or address issues brought up by fire officials.

An inspection of the fire area used to heat the cantaloupe-sized rocks that were taken into the sweat lodge determined it "would have been a legal fire," Doerksen said.

"Where they had the fire, they had a big area outside of it that was cleared," he said. "There wasn't a risk of it spreading someplace."

The sheriff's office is investigating to determine if criminal negligence played a role in the deaths or illnesses. Tests for contaminants ruled out carbon monoxide poisoning as a cause.

Autopsies on Brown and Shore were conducted, but the results are being withheld pending additional tests.

Sweat lodges — used by American Indian tribes to cleanse the body and prepare for hunts, ceremonies and other events — are a common practice in the area. Most are on private property and hold no more than a dozen people, Doerksen said.

Large-scale sweat lodges appear to create a "new challenge for us," he said.

Talks are planned between his department and county officials to consider issuing health warnings for events such as sweat lodges that would include suggestions on how long to stay in.

"It's the same with hot tubs and saunas," Doerksen said. "Most of the time in a motel, it will say do not stay in there more than 10 to 15 minutes. What we're looking at is the same kind of thing."