Massive fireball engulfs Canadian firefighters

Three Canadian firefighters are lucky to be alive after a massive fireball engulfed them while they were attempting to extinguish a building ablaze.

The mobile phone footage shows the fire crew standing atop the building and on aerial ladders while battling to control a violent gas fire, when a backdraft causes a fireball to explode out of the burning building’s roof.

Luckily, nobody was injured in the incident.

"I saw the video of it and it's quite spectacular," Moncton Fire Department chief Eric Arsenault told CBC News.

"It's amazing that nobody got hurt, because we could have easily lost three firefighters as a result of that gas explosion underneath the peak roof."

The blaze started at approximately 11.45pm on Sunday evening with around 20 firefighters from four different stations across the New Brunswich city of Moncton called into action.

The fire is believed to have broken out between the first and second floors of a nearby specialty food store.

Fire damage was so extensive that the building was demolished later in the day.