Investigators are probing the cause of a fire at a compressed gas facility in Brampton, Ont. that caused booming explosions late Wednesday night.

A male employee is recovering from minor burns to his legs after a small fire ignited a group of propane tanks he was filling at a commercial building at 1700 Steeles Ave. E. shortly after 9:30 p.m.

Emergency crews were called to the scene of the a two-alarm fire near Steeles Avenue East and Dixie Road, when nearby residents reported hearing loud explosions.

Peel Regional Police told CP24 that the explosions occurred after a small fire started near the back of the Air Liquide Canada facility, in an area where employees fill 20-litre propane tanks from a larger tank holding about 70 litres.

One witness said he saw about five of the propane cylinders, each weighing about 30 lbs. and slightly larger than those used with barbecues, explode and shoot up into the air.

The fire at Air Liquide Canada Inc. started small, but grew quickly after the tanks exploded.

Firefighters directed most of their efforts to the 70-litre propane tank to prevent a larger explosion, Brampton Fire Investigator Gary Jarrett told CP24.

Air Liquide Canada Inc. supplies hydrogren, propane and other gases to oil refineries, electronics manufacturers and more, so there were other compressed gases on site, but firefighters managed to keep the blaze from spreading to other nearby tanks.

Brampton Fire said the blaze was under control by midnight, but wasn't completely put out until approximately 4 a.m.

At the time of the fire, neighbouring businesses were evacuated as a precaution, but officials said there was no danger, chemically or otherwise, to residents living nearby.

Steeles Avenue East was closed for hours between Dixie and Bramlea Roads, as was the CN Rail track in the area, but both were reopened early Wednesday morning.

Brampton Fire officials told CP24 they will continue to look into safety and training policies at the plant to figure out how to avoid similar incidents in the future.

The Ontario Office of the Fire Marshal is investigating the cause of the fire.