Worker critically injured, homes evacuated after industrial explosion and fire in St. Catharines, Ont.

A man wascritically injured andanother person was taken to hospital as emergency crews responded to a series of explosions and fireat a hazardous waste facility in St. Catharines, Ont., on Thursday.

The explosionstriggered the evacuation of nearby homes for most of the day as crews worked to put out the large blaze.

Police said emergency crews were called to the Ssonix Products facility at 20 Keefer Rd. just after 6:30a.m. ET. The company's website said itsline of business includes producing gasoline, kerosene, distillate fuel oils, residual fuel oilsand lubricants.

Crews found a fire that had spread to a neighbouring industrial building as well.

Karen Lutz-Graul, deputy chief of operations with Niagara Emergency Medical Services, told CBC Hamilton that one person with life-threatening injuries was transported to hospital.

WATCH |St. Catharines mayor gives update on industrial fire:

St. Catharines mayor gives update on industrial fire

2 years ago

Duration 1:51

St. Catharines Mayor Mat Siscoe provides an update on a fire at an industrial facility in the north end of thecity.

A second person "with a serious complaint" was also taken to hospital,Lutz-Graulsaid.That individual did not sufferaphysical injury.

'Black plume' of smoke

St. Catharines firedepartment Chief Dave Upper said the injured man was working at the hazardous wastefacility andthe only person there at the time of the explosion.

"We know the patient is conscious but has received significant burns," Upper said. "We're still working defensively on the fire."

Upper said the injured man was initially taken to a local hospital, but has since been transferred to the burn unit atSunnybrook Health Sciences Centre in Toronto.

A neighbourhood north of the facility was evacuated due to a"black plume" of smoke blowing toward the area, Upper said, withresidents sent to a community aquatics centre.

Shortly after the explosion, police tweeted: "Officers [are] evacuating nearby homes and businesses."

They said residents should "stay indoors, out of the smoke."

Around 5 p.m., Upper said while fire crews remained on scene, thefire was "now under control" and theywere putting out "hot spots."

The Ministry of the Environmentconcluded theair quality was"clean and safe" for workers andresidents, Upper said, announcing the city wasallowingresidents to return home.

The access roads into the neighbourhood have reopened, he added, though Keefer Road remained closed.

Fire crews heard multiple explosions

Early Thursday morning, fire crews heard multiple explosions at the facility for about 45 minutes after they arrived, Upper said earlier in the day. The owner of the facility was on thescene and had told fire crews about various chemicals thatwere in the building, he said.

"We are concerned that there are some cleaning agents in the one bay and we're trying to determine the level of the fire, how far it's extended and our exposure to that area," he said.

Crews were also trying to ensure run-off water from their effortsdidn'tcollect in nearby Lake Ontario, Upper said, and a hazardousmaterials company has brought in marine-containment booms.

"We're working to stem the water from flowing into the lake, andthen whatever's into the lake right now we're trying to capture."

Utter said about 50 residents had been housed at the St. Catharines Kiwanis Aquatic Centre before determining the neighbourhood was safe.

One evacuee, BrunoCaciagli, told CBC News onThursday afternoon, before people were allowed to return home, that he was preparing his breakfast when the explosion occurred.

"The house shook as if we're in the middle of an earthquake,"Caciagli.

He said he heard "a second explosion, not as loud as the first, and it did not shake the house like the first one. And then one minute after that, another explosion ... the sky turned absolutely red. It was like watching the sun coming up on a clear day."

Another resident, Carol Green,saidherhusband was walking theirdogs when they "heard a loud bang followed by a huge orange glow in the sky."

Green said this was "followed by more explosions."

"I was at home," she said, about fourkilometres away from the explosion."[And]the whole house shook."

Residents were told to shelter in place

St. Catharines Fire Services said earlier in the daythat people living in the area outside of the Blossom,Parkside orMoes subdivisionshouldshelter in place.

"Close your windows and doors and turn off your furnace to avoid letting air get in," a tweet from the service read, before the city said the air quality had determined to be safe.

Additionally, St. CatharinesFire Services saidthe Ministry of Environment, Office of the Fire Marshal, Technical Standards and Safety Authority, and a hazmat remediation team hadall been contacted and wouldbe attending the fire.

Gary Wheeler, spokesperson for the Ontario Ministry of the Environment, Conservation and Parks, said thatprior to the fire, Ssonix did not have any ongoing environmental compliance issues.

Wheeler saidministry staff will continue to ensure the fire-douse water is managed properly, and the property owner was taking steps to ensure any impact to the environment is remediated.

"We are monitoring air quality in the area to support emergency services for the duration of the emergency, and we will ensure that the appropriate assessment of impacts to soil, groundwaterand surface water is undertaken, and any necessary cleanup is completed." Wheeler said.