A massive blaze at an auto wrecking yard in Saskatoon's West Industrial area kept fire crews busy Tuesday.

Firefighters and police were first called to the fire at Avenue P South and 14th Street at about 5:30 p.m.

Witnesses reported seeing about five kids in the area lighting tires on fire, according to police.

About 25 firefighters and eight fire trucks were called to the blaze, according to the Saskatoon Fire Department.

The fire sent thick smoke billowing into Saskatoon’s sky for several hours. The smoke was visible across the city.

The fire department said more than 1,000 vehicles were in the compound. Fighters weren’t able to control the blaze until about 11:15 p.m., and crews were still on scene Wednesday morning extinguishing spot fires.

Fighting the blaze was difficult because the scrap vehicles were stacked on top of each other, said assistant fire chief Dave Bykowy. Plastic in the vehicles fuelled the majority of the flames, and airbag canisters were exploding and creating popping sounds.

"Because the vehicles are stacked five-high upon one another, the fire is spreading very quickly," Bykowy said Tuesday. "All fluids have been removed from the vehicles, but the plastic material in them is providing a volatile fuel source."

A crowd gathered to watch the blaze almost immediately after flames broke out. Police officers on scene cleared people away and the service asked residents to avoid the area.

"Road closed" signs blocked several streets in the area, including Avenue P between 11th Street and 20th Street.

Saskatchewan environment officials also responded and conducted air quality analyses.

The owners of the auto yard say the inventory is valued at about $250,000, according to the fire department.

Police said Wednesday five boys between eight and 14 years old were detained for questioning and later released to the custody of their parents.

No charges have been laid.

CTV crews were on scene. Read our live coverage from Tuesday night below:

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