Reclusive British artist Banksy is loose on the streets of New York, hosting a unique show that has whipped up excitement in the bustling US city.

The England-based graffiti maestro, who has never been formally identified, has promised to unveil a new piece of art on each day of the month somewhere in the city.

His stencilled designs, known for their irreverent humour and political activism, have propelled him from a graffiti rebel to reluctant star whose work sells for hundreds of thousands of dollars.

But the New York show is free, public and accessible to all.

Painted in secret and announced online, fans rush to track down the elusive piece before they are painted over or "tagged" by rival graffiti artists, often within hours of going viral.

And the name of the show? Better Out Than In.

"It's just so intriguing, it's like a chase," says actor Lisa Rowe-Beddoe, who has visited each of Banksy's three pieces to date. Her mission is to track them down the full set by the end of October.

The New York show has an Instagram account, which already has about 30,000 followers.

His website, banksy.co.uk, posts photographs of the work and a Twitter feed posts cryptic messages.

looking fwd to getting my hands dirty tonight... #banksyny — banksy (@banksyny) October 1, 2013

The latest piece - a dog urinating on a fire hydrant with the words "You complete me" in a speech bubble - attracted a huge crowd on Thursday.

Teenagers, artists and professionals gathered to chat, joke and snap pictures on their phones - posing for the camera as they crouched down and pretended to stroke the dog.

"It's a buzz," says Ken Brown, who writes a blog about street culture as he takes pictures of the crowd. "And because he's so well known, it'll be a boon to New York".

Mr Brown says he was bitterly disappointed when he got to the first Banksy, which appeared on a wall in Chinatown on Tuesday, to find it was already buffed.

"I'm a long-time admirer of Banksy. I feel he's really a rarefied genius. He gets humour and puts a lot of things that are missing into his pieces," he said.

Fans can access an audio commentary from a toll-free number inked to the ground, or on the website.

The narration from a man with an American accent, introduced by the kind of music played in elevators, is clever and languid.

"Are you looking at one of the great artworks of the 21st century? If so you're in the wrong place. You should be looking at a stencil of a dog peeing on a hydrant," he said of the third artwork.

"It's a well-known truism that the mark of a great artist is their ability to capture light, so you will note that this piece is rendered entirely in silhouette."

Banksy's views on the exorbitant sums paid for his art have been expressed in the Oscar-nominated documentary Exit Through The Gift Shop, and people can download for free photos from his website.

AFP