'Lost' Banksy is withdrawn from auction

Mystery deepens over work that disappeared from Poundland wall

A picture, it is said, is worth 1,000 words. So the rat holding up a sign saying "Why?" stencilled next to the empty space in north London where one of Banksy's murals stood until recently is more than eloquent. On the other side is another sign warning: "Danger. Thieves."

The world's best-known street artist brightened up Wood Green, in north London, when he painted Slave Labour on a wall at the side of a Poundland shop. Showing a young boy hunched over a sewing machine making Union Flag bunting, it appeared last May, just before the Diamond Jubilee celebrations.

Two weeks ago, it vanished. Nothing more was heard of it until it popped up on an art auction website in Miami. The building's owners had apparently realised they were sitting on a goldmine.

Haringey council launched a campaign to bring it back and called on the Arts Council and Culture Secretary, Maria Miller, to intervene. Then, last night, as the hammer was due to fall on the auction, the artwork was suddenly withdrawn from sale.

It was believed the work had not even been in Miami: the masonry enclosing it needs to be stabilised and properly prepared – which could take months.

The IoS photographer Justin Sutcliffe, who was asked to provide a photographic record of two Banksy pieces, Stop and Search and Wet Dog, from Bethlehem on sale in the US, said: "I was asked to take photos as there is no certification process, and to provide a record from packing to delivery."

Both were created around 2007 in the West Bank on the Palestinian side of the Israeli security wall. The pieces weighed 2.5 and 1.8 tons. "I can't see how the current Banksy is in Miami," Mr Sutcliffe added. "It took 10 days to go from the port to the cargo ship alone. So to get that to the US so quickly would be impossible."

Police in London said they had "been in touch with US authorities about the ownership of it and advised them that there has not been a theft". Solicitors acting for Wood Green Investments property firm, owners of the Poundland site, said they had advised their client "to say nothing".