Multiple injuries reported as Mega Bus crashes in Illinois

(Photo: KSDK-TV)

A double-decker bus plowed into a bridge support Thursday in southern Illinois, injuring several people and closing an Interstate highway in both directions, state officials told NBC News.

The exact number and severity of the injuries remained unclear, but at least 18 ambulances and several emergency helicopters responded to the scene on Interstate 55 a few miles north of Litchfield.

Update, 4:35 p.m. ET: At least 23 people are injured, state officials say.

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