CHICAGO (CBS) — Nearly a dozen suburbs sent firefighters to a South Elgin daycare center early Wednesday morning, to help extinguish an extra-alarm blaze.

The KinderCare center at 1250 W. Spring St. was not open yet when the fire started around 5:30 a.m., and no one was inside, according to South Elgin and Countryside Fire Protection District Chief Bill Sohn.

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No students or staff had arrived at the daycare for the day at that point, and no injuries were reported.

Jeff Parke saw the massive blaze from the balcony of his apartment a couple blocks away.

“We were actually concerned about the vet clinic right here, and worrying about the animals,” he said.

Cleveland Veterinary Clinic is located next door. When Parke realized it was the KinderCare on fire, not the clinic, he began recording on his iPhone as the flames got worse.

“I did see the roof collapse, and there was a big fireball that came out,” Parke said.

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Sohn said it appears the fire started on the outside of the building, spread up the side to the attic, and destroyed the roof, causing extensive damage to the rest of the building.

“It’s extensive. We haven’t had a fire this big in a while,” he said. “It’s all wooden trusses in there, so it got a good head start.”

Ten other suburban fire departments were called in to help douse the flames, according to South Elgin spokeswoman Kim Wascher.

Stunned employees showed up later in the morning to survey the damage.

Sohn said it’s unlikely the KinderCare will reopen anytime soon. The company did not immediately respond to requests for comment, but Wascher said parents were notified to take their children to another KinderCare center.

“There are three KinderCares regionally; there’s just another one located approximately three miles from here,” she said.

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The cause of the fire was under investigation. South Elgin Police Sgt. Mike Doty said investigators will review security camera footage from other businesses as part of the investigation.