Mike Dewal, a resident in the building in the 700 block of East Broadway, just east of Fraser Street, said he smelled something like campfire smoke around midnight.
"About 10 minutes later, one of my neighbours knocked on the door telling me there was a fire," he said. "My first instinct was to wake my girlfriend up and get her out of the house, and then run around the rest of the apartments and wake up anybody I could. One family in the apartment above me was passed right out and the only reason they woke up was because I went and knocked on the door.
"I pulled the fire alarm as soon as I made my way back downstairs," Dewal said.
Assistant Fire Chief Joe Foster said the fire department got the call at around 12:05 a.m. PT, and a crew turning onto Broadway from Victoria Drive could see the building was already fully engulfed.
"I think it had a really good hold of the building before we got here," Foster said.
Firefighters went inside and got several people out who hadn't already responded to the sound of fire alarms or to the sounds of their neighbours.
"I talked to one gentleman. They woke him up, and he was very grateful they were able to wake him up out of his sound sleep and get him out in time," Foster said.
Foster said it's not clear whether the alarms that woke some residents up were inside the burning building, or in one of the neighbouring buildings that were damaged by fire, smoke, and water.
Battalion Chief Terry Nikolai told CBC News he also knew of one woman in the building who went door to door, trying to get her neighbours out.
One individual she spoke with was reluctant to leave, and is still unaccounted for, but Nikolai said he is optimistic the man made it out.
Foster said around 40 firefighters ended up at the scene, but the crews were eventually withdrawn from the main building, which had grown too hot.
"We are letting it burn through the roof at this time, mainly just to allow it to vent and that way we can get at the seed of the fire," Foster said.
The cause of the fire is not known, and fire investigators will access the building once it cools down.
At least 16 people have been displaced by the fire.
Google Map: 750 E Broadway, Vancouver