AURORA, Colo. — There is "no reason to believe" that the cause of an explosion at an apartment complex was malicious in nature, Aurora Fire Rescue said on Monday.
Firefighters were still investigating the Saturday morning explosion at Parkside Collective, 14565 E. Alameda Ave., that displaced hundreds of people. That investigation was expected to last several weeks, Aurora Fire said.
Aurora Fire tweeted at 9:57 a.m. Saturday, "Aurora Fire Rescue crews responded to reports of smoke conditions in multi family residential structure. On arrival, crews began searching for hazards when an explosion occurred. Searches and evacuation in progress, damage to the building is being assessed."
AFR asked the community to stay away from Parkside Collective or to evacuate the area as crews investigated the extent of the damage.
An AFR spokesperson told 9NEWS three people were injured in the explosion. All three were taken to the hospital with minor injuries and were expected to be OK.
Around 300 to 400 residents were temporarily displaced due to the explosion. AFR worked with the Red Cross and building managers to find those people a place to stay. The Red Cross opened an evacuation shelter at Gateway High School.
Before the explosion happened, residents said they heard strange noises that were difficult to describe.
"At first I heard some cackling and I thought it was just like the fan, so I turned that off and it stopped for a bit, but then we heard it cackling again," said Joe Bham. "Almost if you're ripping up paper, when you're crumbling paper. So, I thought it was a fan unit or something."
He said they tried to investigate where the sound was coming from, but couldn't figure it out.
"First of all, my fans just stopped working. It was starting to do a wobble noise," said resident Ash Fox. "Instead of a straight fan noise, like white noise, it was going in and out, in and out. It sounded like it lost power but then it gained power again. So, it was just a weird stuff going on with electricity before it happened."
"My voice started shaking and I was shaking for a while," said Fox. "It really shook me up."
Residents said there weren't any flames, only white smoke.
On Saturday night, she had to stay somewhere else, along with other residents, as investigators tried to determine the structural integrity of the building.
"Try not to worry too much about this, but I know I will be," Fox said. "I just hope that everyone's OK."
In the case of Samuel Levy, who was walking to the leasing office, he described the ground shaking.
“The ground started to shake below the apartment building – at that point we decided to make our way outside," he said. “We walked outside, we noticed some steam coming out of the concrete coming in through the separation in the concrete."
Then, that's when the fire alarms went off. AFD said they were called out because a resident saw smoke.
"So ran down here, stood by the grassy area and we saw smoke coming out of the little vents and then I think 10-15 minutes later, it exploded," Bham said. "All the debris just fell off. There was an ambulance right in front of us and I'm pretty sure someone got hit, but it was just crazy."
AFD said the explosion happened near electrical equipment, the elevator and what looks like utility meters.
Across the street at BJ's Restaurant and Brewhouse, a few employees witnessed the explosion as they were preparing the restaurant for the day.
“Soon as I opened the door I could hear the sirens across the street, a lot of commotion with police, the fire engines," said Joe Dean, a senior kitchen manager who was joined by his co-worker, Ryan O'Dea. “Ryan and I both kind of felt the impact in our chest from that explosion."
AFR said the exact origin of where the explosion came or what it was from is unknown, but searches have been negative. Firefighters have mitigated hazards and are out of the building and are waiting for assistance with utility control.
As of Saturday night, 9NEWS had not received a response from Parkside Collective's property management company.
Aurora Fire Rescue investigating explosion at apartment complex
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