10/30/2013 05:39 EDT | Updated 12/30/2013 05:12 EST

Edmonton Rutherford Condo Fire Set On Purpose: Investigators

EDMONTON - Police and fire investigators say a blaze that destroyed a condominium project under construction in Edmonton's southwest was deliberately set.

The fire on Sept. 29 in the Rutherford neighbourhood resulted in $20 million in damages.

That makes it one of the costliest fires in Edmonton history.

About 80 firefighters were seen to fight the flames, which took seven hours to bring under control.

No one was injured.

But neighbouring homes had to be evacuated due to intense heat and exploding propane tanks.