Traffic near Junction 29 for Romford and Basildon on the M25 at 12.25pm. (Image: Traffic England / www.motorwaycameras.co.uk)
Protesters near the Queen Elizabeth II Bridge (QE2) at the Dartford Crossing are causing traffic chaos on the M25.
Southbound traffic on the motorway is currently backed up between junction 29, near Upminster, and junctions 1A and 1B on the other side of the Thames.
Protesters are believed to have glued their hands to the road in some places.
It's understood the protesters are members of Insulate Britain, which is campaigning for "leaky homes" to be insulated, starting with social housing.
Highways England currently says normal traffic conditions should return between 1.45pm and 2pm, when the incident is expected to be cleared.
Kent Police have so far arrested 21 people on suspicion of obstructing the highway.
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