Motorists are advised to avoid the A602 near Stevenage as a traffic incident is causing delays.
Police are at the scene directing traffic on the A602 between Watton At Stone and Bragbury End.
According to Herts Highways, there have been reports of a collision affecting northbound traffic.
It is understood there is heavy traffic in both directions near Hooks Cross due to a broken down car.
More to follow.
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