By Conor McCue

BOULDER, Colo. (CBS4)– Fire investigators will return to the scene of a massive fire at an apartment complex in Boulder on Wednesday. The fire on Tuesday impacted more than 80 units and caused three buildings to collapse.

On Wednesday afternoon, officials said all residents have been accounted for. They add they “are cautiously optimistic that there were no fatalities.”

Firefighters had to forcibly get inside some units to make sure no one was inside.

“This was truly an example of public safety partnership,” Boulder Fire-Rescue Chief Michael Calderazzo said. “This fire burned hot and fast. The ability to get people out of harm’s way quickly made all the difference in terms of injuries and lives lost.”

Boulder Fire Rescue responded to a large structure fire at Whittier Apartments at 2301 Pearl Street just after 3:30 a.m. Tuesday.

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It took two hours for dozens of firefighters to get the fire under control. The 81-unit complex is spread across six buildings. Most structures within the complex have either partially collapsed, collapsed or are structurally unsound.

The fire damaged the top floors of the buildings the most. Some people on the second and third floors jumped to escape the flames.

“[We] got our cats in the bag, police man comes, tells us to get out, and we run,” said Lucy Mills, a resident of the complex. “There were no alarms, I didn’t know until the very last second when I had to get out, which was terrifying.”

(credit: CBS)

On Wednesday, Mills and her husband Jorge Diaz were among the many residents returning to the complex to get a look at their unit. They tell CBS4 their third floor condo, which they had lived in for more than two years, appears to be a total loss.

“It’s really surreal feeling because this had been home for a really, really long time,” Mills said. “Now it’s gone. The only thing to do is to move on and look at new places.”

Alexandra Duprey and her family also believe their temporary rental unit is destroyed. They’re currently staying in a hotel and said they lost laptops, phones, wallets, and more in the fire.

“It looks like the third floor is completely destroyed,” Duprey said. “Our apartment was on the second floor kind of right on the end over here and it looks like it’s gone.”

The structures aren’t safe enough for residents to go back inside. The property will remain closed to the public.

Anyone who lives at Whittier apartments or has stayed there in the past is asked to call Detective Sharon Ramos at 303-441-3323.

(credit: CBS)

Anyone who has been displaced by this fire should go to the Boulder Police Department, located at 1805 33rd St Wednesday from 8 a.m. to 4 p.m. to connect with staff from the American Red Cross.

For more information, please go to redcross.org/donate, call 1-800-HELP NOW (1-800-435-7669),  or text REDCROSS to 90999.

Conor McCue