Fire at old school in West Town intentionally set, officials say; Chicago police investigating

CHICAGO (WLS) -- Investigators say a fire at a former West Town school that prompted a massive response on Monday evening was set on purpose.

Now, Chicago detectives are getting involved.

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More than 100 firefighters responded to the building near West Maypole Avenue and North Western Avenue.

Firefighters had to strategize how to put the fire out because of all the smoke. They also said a group of people inside may have started the fire.

"Somebody said they saw kids running away as the generator came out. It was hard to get to and see and ventilate," one firefighter said.

One firefighter was treated for heat exhaustion, but is expected to be OK.

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