CHICAGO (AP) — A shuttle bus has struck a concrete barrier on a road at O’Hare International Airport, clogging traffic heading to one of the terminals at the start of the busy Labor Day travel period.

Chicago Police Department spokeswoman Ana Pacheco says 15 people were taken to hospitals. She did not have information on their conditions.

The accident took place around 6:30 a.m. about a half-mile from the entrance to Terminal 1.

The accident caused a lengthy backup on a busy roadway into the airport. Air travelers desperate to catch flights were getting out and walking to the terminal.

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