A serious crash forced police to shut the A505 Beech Hill road between Hitchin and Luton this morning (April 28).
During the incident, a black Kia Sorento estate hit a pedestrian.
The duel carriageway had been shut by officers in both directions, but is now clear.
At the time, the police had asked motorists to avoid the area, using alternative routes wherever possible.
A spokesperson for Hertfordshire Police said: "The A505 Beech Hill between Luton and Hitchin has been closed while emergency services deal with a serious road traffic collision.
"Police were called just after 2.20am on Thursday 28 April to reports that a black Kia Sorento estate car had been involved in a collision with a pedestrian.
"Please avoid the area."
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