Art expert Amy Griffin says the Tate Modern should be equipped to restore the mural back to its original state. But how hard that will be depends on whether paint or marker pen has been used.
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Tony Davies was the first civilian to reach Pc Palmer after he was stabbed during the Westminster attack.
Defiant Londoners put on a show of solidarity for the victims of the Westminster terror attack at a vigil in their honour.
Weather set to improve with plenty of sunshine by Saturday