Fire officials in Toronto say they will be “actively firefighting” for the next 24 to 48 hours following a massive fire that erupted early Friday at an industrial building in the city’s west end.

Toronto Fire Deputy Chief Jim Jessop said Friday morning “This is one of the more significant fires we’ve seen in the city in the last number of years,”.

Officials say crews were called to 35 Vulcan Street, which is near the intersection of Martin Grove and Belfield roads, at approximately 1:15 a.m..

At its height, the blaze was classified as a six-alarm fire, and more than 100 firefighters were on scene, as well as crews from police and paramedics.

Just before 8:30 a.m. Friday, the fire was downgraded to a three-alarm fire

According to officials, the fire initially broke out in adjacent tractor trailers before the building itself caught fire.

Toronto Fire was primarily focused on containing the fire due to a high number of combustibles on site, including “thousands of litres of lubricants” and a neighbouring lumberyard.

Toronto Fire said that the incident is being treated as a “full hazardous materials response,”.

The Ministry of Environment was notified about this incident and no injuries have been reported.

Local businesses and residents have been advised to keep windows closed and shelter in place if possible.

The damage to the building is estimated to be in the millions of dollars, but Jessop says he believes it’s too early to say specifics.