Nottinghamshire Police say a protest by 15 campaigners, staged inside two chimneys at West Burton power station near Retford, is costing £20,000 a day to police.
The campaigners say they plan to camp inside the chimneys for a full week and this morning have taken to flying kites and tweeting pictures.
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Rather cloudy with occasional outbreaks of rain, or showers.
Rather cloudy and feeling cool, with a freshening northwesterly breeze.
Pollen levels will rise towards the end of the weeks as warmer weather sets in.