Investigators in Mississauga are working to determine what caused a one-alarm fire that destroyed five tractor-trailers and an SUV overnight.

It happened outside of a commercial building in the area of Atlantic Drive and Britannia Road shortly before 10:30 p.m.

At the height of the fire, members of the Peel Regional Police Service and Peel EMS were on scene alongside the Region of Peel Spills coordinator. Eight fire trucks responded, one support vehicle and one command officer responded to the blaze. The hazmat unit was also called to the area to block drains.

The fire ripped through five tractor-trailers and an SUV parked in the back of the building but no injuries were reported. Damage is estimated to be at least $1 million.

Mississauga Fire says some of the tanks of the tractor-trailers were filled with diesel so crews are still dealing with a significant amount of runoff.

The Office of the Fire Marshal has been notified but Mississauga Fire has not confirmed if the fire is considered to be suspicious.

Investigators will be looking at video surveillance video in the area.