Douglas Radcliffe, Secretary of Bomber Command Association said that the airmen honoured in the Bomber Command Memorial had died to give people the freedom to live in the UK.
He added: "I can't believe that somebody would do this but they've done it."
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Any mist or fog will lift through the morning to leave another dry day with bright spells and light winds.
A dry day with lighter winds than Tuesday. Occasional bright or sunny spells are likely for most, with the best of these in the east.
The group fled the scene and police want to trace them.