Waterloo Region fire crews responded to a major fire at Parkdale Plaza mall as flames and smoke engulfed shops and prompted an evacuation late Friday afternoon.

Waterloo Region Police and Waterloo Fire received reports of fire at the Dollarama store located in the plaza at 462 Albert St. around 4:05 p.m. As dusk approached three hours later, they were still on the scene trying to limit the fire's spread.

Residents in nearby neighbourhoods were asked to stay indoors with windows closed as thick smoke billowed from the plaza.

Multiple aerial trucks sprayed the mall roof from above as fire officials worked to prevent the fire from destroying other stores. Adjacent businesses received heavy smoke damage.

Police say they are investigating the cause of the fire. (@machei/Twitter)

'Fully engulfed'

"The Dollarama was fully engulfed when the fire officials arrived," said Waterloo Police Staff Sgt. Mike Mercer.

Mercer said the damage to the building is expected to be extensive.

There were no reports of serious injuries, although fire crews and people in the surrounding neighbourhoods were exposed to thick smoke.

Several streets, including Albert Street and Quiet Place were closed to traffic in both directions, Mercer said.

The cause of the fire is unknown. Police say the investigation is ongoing with detectives assisting Waterloo Fire.