'Disappeared' Banksy set to sell for £900,000 A mural which disappeared from the wall of a north London shop last year but resurfaced in an auction in Miami - only to be withdrawn at the last minute - has gone on sale in London and was on Sunday evening expected to raise £900,000. The work, Slave Labour, which depicts a barefoot boy using a sewing machine to stitch union flag bunting, was widely seen as condemning child labour and mocking the impending Queen's Diamond Jubilee when it appeared outside a Poundland store in Wood Green last year. It went on sale in an exhibition hosted by Sincura Group in Covent Garden. The group would not disclose the current owner. But Wood Green's MP Lynne Featherstone was among a growing number of critics that insisted the piece should remain public property. Addressing the owner, she said: "You have deprived a community of an asset that was given to us for free and greatly enhanced an area that needed it. I call on you, and your consciences, to pull the piece from both potential sales and return it to its rightful place.