The owners of the Gaylord Rockies Resort and Conference Center in Aurora where metal ductwork collapsed into a pool area, injuring six, will hire a contractor to investigate what happened, authorities said Tuesday morning.

Two of the six suffered life-threatening injuries. Their condition Tuesday remained unclear. A city spokesman said that, as of late Monday, Aurora officials had been told they were alive.

Gaylord Rockies Resort officials referred queries to Aurora Fire Rescue. And fire officials said Gaylord will look into what happened.

“It is under investigation. Gaylord will have their own independent contractor come out to investigate,” Aurora Fire Rescue spokesman Andrew Logan said. “Obviously, if they feel it is unsafe, they are not going to allow people back in.”

Aurora firefighters went to the resort complex, southwest of Denver International Airport, on Saturday morning after receiving 911 calls. They determined 50 to 100 guests were inside the pool area when the heating, ventilation, and air conditioning system components collapsed. Eight firefighters from Aurora already were on scene conducting training, working in stairwells, and they provided a quick paramedic response in the pool area, according to a weekend news release attributed to Aurora Fire Chief Alec Oughton.

Aurora’s technical rescue crew also determined, Oughton’s statement said, that “there were still hazards present” with a threat “of ongoing falling debris and mechanical systems.”

On Tuesday, Aurora city government officials confirmed that Gaylord as a private property must conduct an investigation — and then apply for city permits after making repairs.

“We remain in touch with Gaylord management as they navigate this difficult situation,” city spokesman Ryan Luby said.

Aurora Fire Rescue “is not equipped and does not have the authority to determine the cause of the structural failure that occurred,” Luby said.

Similarly, city building inspection staffers have limited authority over incidents on private property. However, building permitting staffers conducted more than 60,000 inspections at the resort before it opened in 2018, ensuring compliance with International Building Code standards, he said.

“Once the investigation is completed and Gaylord determines the next steps, they will be required to apply for city permits and submit detailed plans developed and signed by licensed professionals to complete any new work or necessary repairs,” Luby said. And city building inspectors then will make sure the work done meets requirements.

The Gaylord facility includes a 1,501-room hotel and cost $800 million to build. Thousands of construction workers were employed on the project, which was expected to generate $275 million a year in economic activity.