No one was hurt when flames broke out in the four-storey Riverview Place development around 5:30 a.m.
Smoke was billowing from the top of the 50-unit structure when firefighters got to the scene and called in a second alarm.
About ten trucks and 50 firefighters were eventually involved in the battle to stop the blaze.
Some witnesses say they could see flames on a second-floor balcony before crews arrived.
BIG condo fire in Mission this morning. Hope everyone's OK! #yyc
Photo: @PuckMummieMay 26, 2015
Paul LeBlanc, a Calgary Fire Department spokesman, says at least three units were heavily damaged but many residents won't be able to return to their homes for quite some time.
Resident Stephanie Cormier said it was shocking to see how quickly the fire spread.
"It was really, really crazy. By the time I was able to get my cat and run out, the flames were just shooting out."
Alana Chypyha says her unit was one of the ones that was badly burned.
"We just grabbed our cat and our hedgehog and we got out. Our screen door was in flames, we probably got out just in time."
Another resident, Andrea Wilkie, had just moved back into her unit in February after the devastating flood of 2013.
"I had a lot of struggles with my particular insurance company. Our building was hit really hard. I was main floor and it took a year and a half just to get it rebuilt and to get back in. It’s really tragic."
LeBlanc said firefighters managed to contain the fire to one side of the building, but they had to contend with a number of challenges.
"The sheer amount of people in the building, and the large amount of smoke and flames to bring under control, which they did quite quickly," he said.
The cause of the fire is under investigation.
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