Banksy’s iconic Girl With Balloon (2006) attracted feverish bidding in the room and on the phones, racing past its high estimate of £300,000 to hammer at £860,000, or just over £1 million ($1.3 million) with fees. As the gavel slammed, a siren rang out through the salesroom and everyone stood stunned as the Banksy canvas slid through the frame that it was contained in and emerged underneath—but shredded.

It seems that the art world’s biggest prankster concocted a scheme in which his work would get destroyed as soon as it was sold. The spray painted work of the girl with a red balloon, acquired directly from the artist, came in what the catalogue called “the artist’s frame”—a frame that was oddly thick for such a small work of street art.