Graffiti art, by its very nature, doesn’t lend itself well to gallery shows or commercial auctions. So how do you capitalize on the demand for an artist’s work if it exists on the side of a building? An anonymous individual recently answered that question by physically removing part of a wall painted by acclaimed graffiti artist Banksy and putting it up for auction at it an estimated price of more than half a million dollars.

The piece in question, now titled Slave Labor (Bunting Boy), originally appeared on the side of a London budget store in the Wood Green area last May; its imagery was considered a critique of the “real-life” discomfort and sweatshop conditions behind the cosy, nostalgic British iconography of the Queen’s Diamond Jubilee.

The artwork was removed from the store along with a large chunk of the wall last week, as noted by a local resident at the time. It has since appeared on the website of Fine Art Auctions Miami among a number of modern pieces and will be auctioned at the end of this week for an estimated price of between $500,000 and $700,000.

According to Fine Art Auctions’ owner, Frederic Thut, the art is being offered by a “well-known collector” who prefers to remain anonymous, but has apparently provided proof that they own the work in question. (Attempts to reach Fine Art Auctions Miami for comment were unsuccessful.)

Poundland, the store from which the artwork was removed, has tweeted that it is “NOT responsible for either selling or removing the Banksy mural,” adding that it does not own the building in question and has been unable to contact the owner so far to find out more, while local politician Alan Strickland has already launched a campaign for the artwork to be returned.

Talking to reporters, Strickland explained that “Banksy gave this art for free to our community, so we’re all angry that it’s been removed and put on sale for $500,000 in the U.S. We’re trying to track down who is responsible. We’re not certain who removed it, but we’re absolutely certain we want it back!”

With the auction set to take place on Friday, however, the citizens of Wood Green have little time to argue their case. Of course, if all else fails, Banksy could always just paint a new piece about the appropriation of public art in its place.