The A2 was closed in both directions after a major accident near Dartford Heath earlier this morning.
The crash happened at around 9.20am near the junction with Old Bexley Lane.
A 30-year-old man has been taken to Queen Elizabeth Hospital in Woolwich with leg, chest and abdominal pains.
Kent-bound traffic has now been released after congestion was all the way back to the Black Prince Interchange.
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