At least four abseilers were seen descending from the room of Basel's St Jakob Park stadium with a banner protesting against Arctic oil drilling by Russian energy firm Gazprom.
Schalke, the German team playing against Basel, display the Gazprom sponsor on the chest of their playing shirts.
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More than 20,000 allegations of abuse by care home workers have been made in the last three years, figures show.
Two private citizens have already paid a "significant deposit" to take the week-long trip.
Slippy start tomorrow with frost & ice