The A405 North Orbital Road - near St Albans - was closed Southbound this morning, following a crash between a motorcycle and a van.
The incident occurred in the vicinity of the Chiswell Green area, between Junction 21A of the M25 and Junction 6 of the M1.
Hertfordshire Police put road closures in place to allow emergency services vehicles access to the crash.
The police also advised motorists to avoid the area, finding an alternative route where possible.
A spokesperson for Hertfordshire Police said at the time: "Police were called shortly after 8am today (April 25) following a road traffic collision on the A405 North Orbital Road near Chiswell Green.
"It was reported that a motorcycle and a van were involved.
"Officers are currently on scene alongside the ambulance service and road closures have been put in place.
"Motorists are asked to please avoid the area at this time."
A spokesperson from National Highways added: "The A405 southbound between the M25 J21A and M1 J6 is closed due to a serious collision. Traffic is being diverted via local routes.
"Emergency services are on scene. Please take care on approach."
For the most up-to-date information about the county's roads, visit our LIVE Hertfordshire traffic map.
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Do you have a live or breaking news story from across Hertfordshire? Email: hertslivenews@archant.co.uk
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