According to officials, a gas leak in the northern suburbs of Chicago Thursday morning, causing the persistence of a toxic cloud for several hours. Seven people are in critical condition and several others have been hospitalized because of this gas leak.
A tractor pulling two 2-ton containers of anhydrous ammonia around 4:30 am was drilled in one of the tanks, creating a chemical cloud, Lake Forest Fire Chief Mike Gallo announced.
Thirty-seven people were hospitalized after the leak, many suffer from respiratory problems. According to the Lake County Sheriff's Office, eleven firefighters were among those sent to the hospital.
Three law enforcement officers were in good condition and several others were in serious but stable condition.
Authorities did not reveal the cause of the leak.
During the flight, residents of a one-kilometer radius were asked to stay inside and close their windows while the schools were closed for the day.