The fire started on the deck of a third-floor apartment, according to a spokesperson for the Town of Morrisville.
Someone called for help just before 2 a.m. and residents were surprised at how quick it arrived.
"The fire department came and got it done, but there was some pretty serious flames," resident Brett Jarrett told Eyewitness News.
Jarrett lives in the building next to the one that caught fire. He said the flames were leaping through the roof and reached 20 to 30 feet in the air when firefighters arrived.
About 50 people were evacuated and most of them won't be able to live in their units anytime soon. Camden Westwood managers say they should be able to house those residents in vacant units in other parts of the complex.
Thanks to properly working smoke detectors and alert neighbors, no one was injured.
"First thing you hear is the fire alarm go off and you, you know, you take your time, get outside, then you see the building next door on fire," Jarrett explained. "And, uh, you start to get real serious real quick and try and make sure, you know, anybody you know is out of the building."
Although all of the residents escaped, one of them left a cat behind. Firefighters rescued it and reunited the pet with its owner.
There are sprinklers in the apartments, but their effectiveness was limited because the roof collapsed and knocked the system out.