When a collection of the stencil artist Banksy's work was sold at auction last year, Sotheby's said it was unusual for the company to see works with "spray paints". But Banksy collectors who saw works from Britain's most prominent stencil artist sell for more than £50,000 apiece are now cashing in, and selling up.
Sotheby's will hold a second sale of seven artworks by the 32-year-old Bristol-born artist, including Bombing Middle England, which depicts bowls players as bombers, and is estimated to reach between £30,000 and £50,000.
Cheyenne Westphal, the chairman of contemporary art for Sotheby's Europe, said: "Banksy is an exciting artist and we are delighted to be offering further works by him. He has an unnerving ability to get to the heart of the matter and is able to express strong political statements with poetry, energy and humour."
Banksy came to the fore in 2003 with his exhibition Turf War, and by last year his mainstream recognition - and celebrity following - was confirmed when the Hollywood actress Angelina Jolie was reported to have spent more than £200,000 on a stencil, and the singer Christina Aguilera also became a collector.
In October last year, Banksy's set of pictures of the model Kate Moss, reminiscent of Andy Warhol's work, sold for £50,400, five times the guide price, and his stencil of a green Mona Lisa sold for £57,000.
The seven works for sale in February are expected to exceed £167,000 in total. Sotheby's described them as typical of his anti-war and anti-establishment style, and include the sculpture of Ballerina with Action Man Parts and Bomb Hugger, a stencil of a girl hugging a torpedo bomb.
Banksy, whose stencils appear across the south and east of London, closely guards his true identity: his parents still believe he is a painter and decorator. Operating in disguise, he has smuggled doctored oil paintings into leading museums. In September last year, he planted a life-size replica of a Guantanamo Bay detainee dressed in an orange-jumpsuit inside the Disneyland theme park in California.
And the subversive artist has exhibited along the 425-mile barrier that separates Israel from Palestinian territories, painting windows with mock panoramic scenes on the concrete canvas. He posted the work on his website with the message: "The wall is illegal under international law and essentially turns Palestine into the world's largest open prison. It also makes it the ultimate activity holiday destination for graffiti writers."
In 2005, he added one of his works to the collection in the British Museum. When the mock primitive cave painting, depicting a hunter pushing a shopping trolley, was discovered, the museum added it to its permanent collection.
Last year, an image of a naked man hanging out of a bedroom window appeared in Bristol city centre. The city council asked residents to vote on whether they wanted the work removed. Ninety-seven per cent of people who voted in an internet poll said they thought it was a welcome addition to the town, and the image remains.
But while he has gained a cult following, there are those who dismiss Banksy's work. The charity Keep Britain Tidy has previously said that his work is simply vandalism. And the cartoonist Charlie Brooker has said: "He's often feted as a genius straddling the bleeding edge of now. Why? Because his work looks dazzlingly clever to idiots."
The sale will take place at Sotheby's in London on 7 and 8 February