A fast-spreading fire tore through a Port Coquitlam neighbourhood Tuesday morning, forcing about 20 people to flee their homes before sunrise.

Firefighters believe the blaze, which was reported around 5:45 a.m., broke out at a residential construction site on Fraser Avenue near Oxford Street. The flames quickly engulfed the home then jumped to two neighbouring properties.

Anastasia Polianskaia, who lives beside the construction, said she only had minutes to escape after the fire woke her up.

"I came out of my bedroom and I just saw this bright, shiny light and my windows started cracking," she said. "By the time I was looking for my cat, within five minutes, it was collapsing down behind me."

Polianskaia said she hasn't seen her cat since fleeing the fire.

Though the cause hasn't been confirmed, fire crews suspect it began at the construction site. Witnesses told CTV News they heard explosions coming from the property, and that there were propane tanks being stored at the site.

"We have an investigator on the way. Anytime you have a fire of this magnitude it's very difficult to determine how it started," said Port Coquitlam Fire Chief Nick Delmonico.

Houses under construction are particularly dangerous, Delmonico added, because they're open and flames tend to spread throughout them quickly.

Fifty firefighters from Port Coquitlam and Coquitlam were dispatched to the neighbourhood to battle the flames, and spent hours trying to get the blaze under control.

One challenge was a gas line that was shooting flames until a crew from FortisBC arrived to dig up the pipe and cap it off.

Three homes were lost and several others were damaged, including two that are located all the way across the street.

Fortunately, everyone managed to escape safely, some thanks to neighbours who banged on each other's doors to make sure they could get out.

With files from CTV Vancouver's Nafeesa Karim