A late-weekend fire at a trucking warehouse in Fort St. John, B.C., sent fireballs high into the air and prompted the evacuation of a nearby trailer park.

The fire began Sunday night, though the cause is not yet known. Fireballs could be seen erupting 150 metres into the sky as the fire raged.

But Fort St. John Fire Chief Fred Burrows told CTV's Canada AM that the fire had been brought under control as of early Monday.

"At this time we have the fire under control and we're proceeding with what we call the overhaul stage," Burrows said in a phone interview just after 6 a.m. ET on Monday.

Burrows said a large number of chemicals are stored within the building where the fire took place.

"Initially, we had contacted the owners of the product in the building and there's approximately 130 to 140 barrels of either methanol products, or acid products, that were burning at the time of the fire, at the high point of the fire," he said.

Those chemicals are the presumed cause of the fireballs, Burrows said.

"Most of that kind of product that has been burning has been extinguished or was consumed by the fire at the time," he said.

The residents of an adjacent trailer park -- where more than 130 mobile homes are parked -- have still not returned home because of the fire.

Burrows said fire officials are still not sure where the fire started within the building, nor what caused it.

Fort St. John is located in the northern part of the province, more than 450 kilometres northeast of Prince George, B.C.

With files from CTV's Canada AM