WAUKEGAN, ILL (CBS/AP) A large explosion has blown the top off a shopping plaza in Waukegan, Ill. Police say at least six people have been taken to a hospital.
The explosion struck around lunchtime Thursday. It blew the windows out of storefronts and collapsed the ceilings above stores.
Witness Candi Rixie was taking orders at a sandwich shop a block away. She said she felt a rumble, almost like somebody hit the building with a car.
It wasn't immediately clear what caused the blast, but crews from People's Gas were on the scene to investigate.
Fire crews from several towns have come to help in rescue efforts, and are searching to see if people are trapped inside.
Television images of the Chicago-area shopping center show a collapsed ceiling above a tuxedo shop, cellular phone store and a hair salon. Authorities reported there are several injuries, reports CBS News station WBBM-TV in Chicago.
Windows of stores were blown out, possibly by the collapse itself or the precipitator or catalyst that caused it, reports WBBM.
Mannequins from the tuxedo store were left strewn about the street.
There was no definitive word on whether people were trapped, but collapse rescue personnel were sent in from all over Lake County with thermal imaging equipment.
Authorities have closed surrounding streets, and gas crews are on the scene because firefighters fear a gas leak, reports WBBM.
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