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ST. LOUIS, MO (KTVI) – An overturned tractor trailer is blocking all lanes of traffic on northbound I-55 near downtown St. Louis. The accident is near the Park Avenue exit. The accident is just before the highway heads from Missouri into Illinois.

The St. Louis Fire Department says that there are multiple vehicles involved in the crash. There are also injuries in the accident. It appears emergency crews are working on extracting the semi truck driver.

Traffic is expected to be backed up in both directions for some time.

Check the latest traffic conditions here:

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