An early morning carbon monoxide call led to 21 residents being sent to the hospital in Bridgeport.
According to Bridgeport officials, emergency crews responded to 22 Oak Street, where people were suffering from CO-poisoning symptoms.
Officials say a generator was found running in the basement, which they say caused a high level of carbon monoxide. The fire marshal's formal investigation is ongoing.
In total, Bridgeport officials say 21 people were taken to St. Vincent's Hospital for evaluation. The extent of their injuries is unknown.
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The Bridgeport Fire Department said that it urges people to run generators outside the home, as high carbon monoxide levels can occur if generators are used in houses, garages or crawl spaces.
The city said a generator was likely being used by residents on Oak Street since power to the building had been shut down due to a recent bus fire nearby.
