The M25 has been closed after a lorry shed its load.
The HGV left the road on the anticlockwise carriageway between junctions 22 for London Colney and 21A with the A405.
Images shared by police officers show debris littered across the carriageway.
Police have described it as a "significant" incident and warn the road will be closed for "some significant time".
RPU South Base
— BCH Road Policing Unit (@roadpoliceBCH) March 5, 2021
M25 Anticlockwise J22-J21. Significant incident with a HGV having shed it's load and left the carriageway. Motorway likely to be closed for some significant time. Please avoid and find alternative routes. Working with @HighwaysEngland to clear the road ASAP pic.twitter.com/K1ZD02CS3y
Hertfordshire Fire & Rescue says it was called shortly after 8.30pm, sending two crews from St Albans. Paramedics also attended.
The lorry struck both a bridge column and a barrier and ruptured its fuel tank causing a large amount of fuel to leak onto the motorway.
The fire service says there are no reports of any casualties.
Trapped traffic is reported to be passing the scene in lane four.
There is a diversion via the A414 North Orbital Road via St Albans.
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