The demonstration happened this morning (credit: Insulate Britain)
Campaigners for Insulate Britain began obstructing the road near Junction 31 for Lakeside at around 8.15am this morning.
They are calling on the government to insulate 29 million “leaky” homes in Britain which are “some of the oldest and most energy inefficient in Europe”.
The group said it would take further action if the government did not make a commitment to reach that target.
Essex Police officers closed the road while they arrested twelve people on suspicion of highways obstruction.
The protesters are currently in custody.
National Highways said there has also been disruption at turnoffs for Heathrow Airport, Swanley in Kent and Godstone in Surrey.
Chief Inspector Paul Austin said: “This incident caused significant disruption and our officers worked to resolve it as quickly and safely as possible.
“I want to thank the drivers affected for their patience and understanding.”
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Tags: Thurrock, Lakeside, M25