Members of environmental campaign group Earth First UK have occupied the proposed site of the west Cumbria coal mine.
The group are squatting at the site near Whitehaven as part of their campaign to stop coal from being taken from the ground in Cumbria.
In a statement on the group's website, they said: "We have chosen to occupy the site of the proposed Whitehaven mine to send a message to those on these isles and across the world: This mine will not go ahead, leave the coal in the hole.
"The world is burning. More and more people are waking up to the reality we are faced with: we must end not just fossil fuels but also the capitalist system that places profit above planet and people."
A group of protestors had clashed with bailiffs at the site. Police are at the scene.
Challenges by campaign groups Friends of the Earth and South Lakes Action on Climate Change were due to be heard in the High Court in October.
The hearing was recently postponed until after the Supreme Court rules on an oil drilling case in Surrey, which could set a vital precedent on whether planning applications should consider the impact of using, and not just extracting, fossil fuels.
Cumbria County Council approved the mine three times before deciding to reconsider the proposal in February 2021.
West Cumbria Mining say the mine will create 500 jobs.
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