Residents took to social media on Sunday night to share photos and express concerns about an apparent fire at Algoma Steel.
Algoma Steel communications manager Brenda Stenta has confirmed that a transformer failure at the plant's power substation resulted in a loss of power just before 11 p.m. yesterday evening.
Stenta says back-up systems were engaged in response to the outage, including the flaring of coke oven gas, and power was eventually restored.
Bright orange flames from this response system could be seen across the city.
She says a previously scheduled maintenance outage was initiated, which allowed for necessary repairs to occur.
Stenta has not confirmed if the transformer failure was due to a lightning strike.
There were no injuries reported, and there is no expected impact to the plant's operations.