Roof collapses on 24-hour supermarket in Terrebonne, Que.

Late-night shoppers in a 24-hour Metro Plus supermarket in Terrebonne, Que., were surprised to hear an audible crack reverberate through the building just after 11 p.m. Sunday.

The store's manager immediately ordered all the clients to vacate the store and called 911.

Firefighters raced to the store, located on Moody Boulevard, and quicklydetermined the roof was in imminent danger of collapse.

The six employees who remainedinside were told to get out and, about 20 minutes later, about a third of the roof collapsed on the fruits and vegetables section.

But, thanks to the quick-thinking manager and local fire officials, nobody was injured.

One store employee told CBC thatnormallythe staff at that late hour are very young. She praised the manager for acting so quickly.

The city's fire chief Sylvain Dufresne said the roof collapse also broke a water pipe, which subsequently flooded the store. Firefighters were able to shut off the water a short time later, but the damage was done.

When the sun rose several hours later, the store was still filled with ankle-deep water. The wind, blowing through the massive hole in the roof, was making the hanging light fixtures sway.

It was the accumulation of snow, ice and water that likely caused the collapse, Dufresnesaid.

The supermarket is closed to shoppers as owners of the business assess the damage. Crews were called to the site to determine how exactly they will clean up the mess and eventually replace the roof.

That collapse was the second in Terrebonne. Earlier Sunday evening, the roof on a vacant commercial building collapsed.

In that case, firefighters smelled gas and shut electricity off to the area, but nobody was injured.

Industrial building collapse

In Joliette, Que., just northeast of Montreal, a substantial portion of a factory complexcollapsed at around midnight but, again, nobody was inside.

The local fire department's division chief,Patrick St-Louis,told CBC it was a building alarm atStrong/MDI, located onRaoul-CharetteStreet, that alerted officials to the issue.

Firefighters quickly ensured all gas, electric and water lines to the building were shut off.

The roof had been completely cleared of snow within the past few weeks, he said, but the accumulation of ice and snow caused the collapse.