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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Cloudy and windy in the East. Cloudy and mild, with patchy rain in West.
Most places dry overnight. Cloudier and windier during Sunday.
Cloudy and mild on Sunday, risk patchy rain in west.