More than forty firefighters battled a fire that broke out late Sunday morning at a storage warehouse in northwest Edmonton.

Fire crews were called to the commercial warehouse in an industrial area near 148 Street and 128 Avenue just before noon.

"When they arrived, there was black smoke coming out of the building," Edmonton Fire Rescue spokeswoman Holly Budd said. "They forced entry and the sprinkler system had been activated in the building." 

Edmonton Fire Rescue Services district chief Marc Zubick said the portion of the building that was engulfed stored edible oils. 

"It's cooking oil that was the cause of the smoke but the cause of the heat that created the smoke on that oil has not been determined yet," said Zubick. 

Zubick said the fire suppression system in the warehouse did a good job keeping the fire from spreading. As a precaution, firefighters called for more fire trucks at around 12:10 p.m., and a second alarm was called around 10 minutes later. 

Forty five firefighters fought the remainder of the blaze for two hours. The cause is still unknown.  

Warehouse fire - smoke

Edmonton Fire Rescue Services district chief Marc Zubick said the smoke was caused by burning cooking oil. (CBC)