City of Edmonton fire investigators said Monday that the cause of a multi-million dollar fire in a northeast condo building was smoking materials that had been tossed into a diaper pail.

The fire broke out in the Avenue complex, located at 301 Clareview Station Drive just before 5 p.m. Friday.

More than 155 residents were displaced by the fire – two firefighters suffered minor injuries on the scene.

Edmonton Fire Chief Ken Block called the fire ‘devastating’ in a statement, and confirmed to CTV News that it started in a diaper pail on a third floor balcony, where a cigarette butt had been tossed.

“It was a container with diaper, diaper material in it,” Block said.

Officials said in a statement the fire was ‘completely preventable’ and said the fire should raise awareness for risks of disposing smoking materials on balconies of ‘large wood-framed, combustible buildings’.

“I am calling on Edmontonians to take responsibility for their actions related to fire use and to exercise good fire prevention practices at all times,” Block said in a statement.

Officials said Friday’s blaze was the second major fire in Edmonton in less than a year that was caused by smoking material that was improperly disposed of.

Flames destroyed a large section of the building – damage has been estimated at $16.3 million.

Edmonton fire told CTV News no criminal charges would be laid against whoever threw out the cigarette butt.

With files from Joshua Skurnik