CHICAGO (CBS) — Fire investigators were in Humboldt Park on Wednesday, trying to determine what sparked a massive blaze that destroyed a large flea market.

Marilu Gianni, like many vendors who work at Buyers Flea Market, showed up to the 4500 block of West Division Street on the day after the devastating fire, hoping to be able to get into what’s left of the building to see if anything inside is salvageable.

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For several hours Tuesday, flames swept through the two-block-long flea market, fueled by the many cars in its large parking lot and auto repair shop, as well as many flammable wares inside the unsprinklered building.

The flea market included a two-level parking garage, and officials said many cars were destroyed in the blaze, including several vehicles that were parked on the upper level and fell into the burning building as portions of the upper parking deck collapsed.

Police were keeping everyone out of the building Wednesday morning. Soke was still billowing from the ruins, and firefighters were still keeping an eye on hot spots to keep the fire from flaring up again.

“Everything is gone. I mean, clothes, shoes. Everything has to be burned, you know?” Gianni said.

For the last 18 years, Gianni has sold jewelry on Saturdays and Sundays at Buyers Flea Market. She said there’s a chance some of her most expensive items were spared, because they were stored in a fireproof safe.

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“When you buy those things, they say that is fireproof, but we don’t know how long, how hot,” she said.

Gianni said going to sell jewelry at another flea market would be very difficult.

“To move, to go to another flea market is to start all over again, because your customers are here. People is going to come and look for you here,” she said.

However, she said she knows starting over is the only option, and she’s trying to come up with ideas so she can cover her family’s bills.

“I’ve been asking God, and praying to God, ‘Give me ideas. Give me the strength to get up and go out again and do it,’” she said.

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Fire Department officials said the cause of the blaze might not be known for several days.